General Question on Physics
Q1. What will be the weight of matter at the moon?
1/6th of what it will weigh on the earth. Eg: If a man weighs 72 Kgs on earth, he will weigh only 12 Kgs on moon.
Q2. What is the SI Unit of mass?
Kilograms.
Q3. What is the SI Unit of Density?
Kg/m to the power of 3 (kilograms per cubic metre)
Q4. The relation between linear and angular velocity is.......?
v=rw.
Q5. A cylindrical coil of wire is known as.......?
Solenoid.
Q6. Watt governor makes use of the ........
Centrifugal force.
Q7. When the coin is dropped, the force acting on it is ..............
Gravitational.
Q8. A flying bird possesses ................................... and ..................... energy.
Potential, Kinetic
Q9. Which law explains the three states of matter?
Hooke's law.
Q10. In liquids, the interatomic force is........
strong.
Q11. What is the density of water?
1000Kg/..............
Q12. Why rain drops or any liquids look spherical while dropping?
Because of surface tension.
Q13. What is natural radioactivity?
Spontaneous emission process.
Q14. What is the use of very high penetrating power of x-ray?
Destroy malignant tumors.
Q15. What happens in an uncontrolled chain reaction?
Enormous amount of energy is relased.
Q16. What is obtained when a neutron converts itself into a proton?
Antineutron.
Q17. Red coloured insulated copper wire in domestic electric circuits indicate.......?
Live.
Q18. Electro magnets are based on the principle of........
Magnetic effect of a current.
Q19. Which colour reflects all of colours of light?
White.
Q20. The properties of solid depend on..............
Arrangement of atoms.
Q21. A blotting paper absorbs ink because of........
Capillary action.
Q22. ..............................is the type of waves produced in water and liquids.
Transverse.
Q23. An electric heater with 1500W capacity consumes ................ energy in 10 Hrs.
15 KWh.
Q24. Which color absorbs all colours of light?
Black.
Q25. What will be weight of the load on the head of a person falling from a high raised building?
Zero ... because the acceleration of his fall is equal to the acceleration due to the gravity of earth.
Q26. The weight of a person is 600N to climb a height of 10m, how much energy he requires?
9.8s.
Q27. Small insects can move about on surface of water. How?
Surface tension of water is large.
Q28. Factors affecting surface tension are.......
Temperature and impurities.
Q29. When a body rotates about a fixed axis, its motion is a .........
rotatory.
Q30. ..............................uses conventional source of energy?
Thermal Power Plants.
Q31. Which colour of light undergoing dispersion travels through the glass With more velocity?
Red.
Q32. The widely used primary cell is.........
Dry cell.
Q33. Liquid is slowly converted into vapour by...................................process.
Vapourisation.
Q34. Evaporation when compared with boiling, it is a ........
slow and calm process.
Q35. On what principle carburetor produces petrol and air mixer?
Bernoulli's theorem.
Q36. When water solidifies to ice, ...................................
Heat is absorbed.
Q37. Why a stick immersed in water appears bent?
Because of refraction of light.
Q38. When the pressure above the liquid is high, the boiling point.........
increases.
Q39. Television occupies frequency bands on either side of ......................region.
Frequency modulation.
Q40. During dispersion, the emergent ray is bent towards........
the base.
Q41. Who invented the phenomenon of dispersion?
Newton.
Q42. When the critical angle of diamond is 24.4 degree, its refractive index will be........
2.42 (Sin 24.4 = 0.41).
Q43. Which rays are detected by thermopile?
IR.
Q44. Cellular phones use radio waves in.........
Ultra high frequency band.
Q45. UV rays are used in the ........
Sterilization of surgical instruments.
Q46. Which colours have the longest waves?
Red and Yellow waves are the longest, and hence are the least refracted.
Q47. Which is the most spectacular example of "dispersion of light"?
Rainbow.
Q48. At any point of time, what does a particle possess?
Energy and momentum.
Q49. Who detected the ultraviolet region?
J. Rither.
Q50. What is the reciprocal of specific resistance?
Conductivity.
Q51. If the distance between two objects id doubled, the force of attraction between them will be........
One fourth.
Q52. The value of gravitational constant is.........
Different at different places.
Q53. Phenomenon of mirages is observed in desert due to........
Total internal reflection.
Q54. Light rays coming from distant object when incident are focused by a ......................rays, are refracted twice.
Plano-convex lens.
Q55. Two bulbs of 100w and 200w have been connected in parallel with 220 V AC Supply. Which bulb has more current to flow through?
200W.
Q56. At what angle must two plane mirrors be placed so that the incident and Reflected rays are alwlays aparallel to each other?
90 degree.
Q57. What is the angle of deviation of a ray, whose angle of incidence is 80 degree?
20 degree.
Q58. An electric bulb is rated 220 V and 60 W. When it is operated on 110 V The power consumed will be........?
30 W.
Q59. To increase both the resolving and magnifying power of a telescope..............
both the focal length and aperture of the objective has to be increased.
Q60. The ionizing power of alpha ray is ................
very high.
Q61. Which rays are absorbed by the ozone layer?
Ultra violet rays.
Q62. The extremely minute particles present in the atmosphere mainly scatter ....................................color of light.
Blue.
Q63. Liquids expand roughly ................times more than solids.
two.
Q64. The apparent random wavering of objects is due to.........
atmospheric refraction.
Q65. Danger signals should be in .............................colour.
Red.
Q66. How does the colours of the rainbow occur?
Due to the dispersion of sunlight by water droplets suspended in the air.
Q67. Why is spring made of steel and not copper?
The elasticity of steel is greater than copper.
Q68. What is used for measuring the wavelength of light?
Interferometer.
Q69. How many times the light ray refracts as it propagates through a Triangular glass?
Twice.
Q70. Electric current is defined as the rate of flow of.........
Charge.
Q71. Ohms gives the relation between potential difference and.........
Current.
Q72. The atoms of all elements are made up of which atom according to Prout's model?
Hydrogen.
Q73. A chain reaction is possible when the mass of the fuel is greater than........
Critical mass.
Q74. Natural radioactivity is exhibited by.........
Uranium salts.
Q75. In which material X-rays produce fluorescence?
Barium platino cyanide and zinc sulphide.
Q76. Gravitational force is a .........
Long range.
Q77. What is the unit of magnetic moment?
Bohr Magneton.
Q78. Why is it easier to spray soap water?
Addition of soap decreases the surface tension. The energy for spray is directly proportional to surface tension.
Q79. Which is more elastic ? rubber or steel?
Steel ? more elastic for the same stress produced in rubber.
Q80. What is "Zeeman Effect"?
Splitting of spectral lines by magnetic field.
Q81. Who stated the uncertainty principle?
W. Heisenberg. The Uncertainty Principle relates to Quantum Mechanics. It states that precise inequalities that constrain certain pairs of physical properties such as measuring the present position while determining future momentum of a particle.
Q82. X-rays are used in the medical field to find........
Any foreign bodies in the human body, like bullets, pins, coins etc.,
Q83. Which is similar to the splitting up of a liquid drop?
Nuclear fission.
Q84. In a Coolidge tube, the angle of anode is inclined to........
45 degree.
Q85. How does the liquid drop held together?
Intermolecular force.
Q86. In a nuclear chain reaction, the number of fissions takes place at each successive stage goes on inducing in..............
geometrical progression.
Q87. The nuclear reactor is surrounded by.............................to arrest any nuclear radiation.
thick lead lining.
Q88. .............................is the nuclear reaction in which energy is used for peaceful purposes.
Controlled chain reaction.
Q89. Gamma rays are ..................................................charged particle.
uncharged.
Q90. What is seen when the discharge tube is covered with thin black card board?
A brilliant glow is seen.
Q91. In what form the coil is attached to specially treated paper in loud speaker?
Cone.
Q92. Why does a piece of chalk emits bubbles when immersed in water?
Chalk consists of pores forming capillaries. When it is immersed in water, the water begins to enter the capillaries and air present there expelled in the form of bubbles.
Q93. What is the SI Unit of pressure?
Pascal.
Q94. Transformer is used to ........
step up or step down alternating current.
Q95. Transmission of AC causes more power loss than that of DC in transmission. True or False?
False.
Q96. ....................................in a DC generator is used for reversing the current.
Split rings.
Q97. Which dimensional copper wire has the lowest resistance?
0.5m of 1mm diameter wire.
Q98. ..............................acts as a negative electrode in a simple voltaic cell.
Zinc.
Q99. The current produced in a conductor when it moves into a magnetic field is called as................
Induced current.
Q100. By increasing the current in the coil and introducing a soft iron core inside the coil ......................
the strength of the electromagnet can be increased.
Q101. .............................is used as a coolant in nuclear reactor.
Heavy water.
Q102. Why does a liquid remains hot or cold for a long time inside a thermos flask?
Because of the presence of air in between the double glass of walls. Air is a poor conductor of heat.
Q103. Why does a ball bounce up on falling?
When a ball falls, it is temporarily deformed. Due to elasticity the ball tends To regain its original shape, for which it presses the ground and bounces up. It is an example of Newton's Third Law of motion.
Q104. What is the magnitude of the force, when a current conductor is placed perpendicular to the direction of the magnetic field?
Maximum.
Q105. During short circuit, the current in the circuit..............................
increase heavily.
Q106. The reciprocal of resistance is known as........
Conductance.
Q107. The other name for Fleming's left hand rule is............................
Motor Rule.
Q108. The total number of magnetic lines of force crossing unit area held normal to the magnetic lines is known as........
Magnetic induction.
Q109. .............................is obtained during the conversion of proton into neutron.
Positron.
Q110. If an electric kettle is marked 220 V, 1Kw, the maximum current at which it can be safely operated is........
4.5 A.
Q111. Watt-hour is equal to ............................J.
3600
Q112. Electromagnet can be demagnetized by........
Switching off the current.
Q113. The rod or stem in a gold leaf electroscope is made up of..............
Ebonite.
Q114. What is the SI unit of Specific resistance?
ohm.
Q115. When a mirror has a focal lenth of +10cm, then it is a ........
Concave mirror.
Q116. The electric current in a conductor gets .......................when the potential Difference across a conductor is doubled.
doubled.
Q117. .............................................................................is how the maximum distance upto which the molecule exerts force of attraction is called.
Molecular Range
Q118. If the velocity of the liquid exceeds the limit, the flow of liquid is.........
turbulent.
Q119. The restoring force per unit area is called as........
Elastic limit.
Q120. What is the melting point of ice on Kelvin Scale?
273 K
Q121. Why is standing in boat or double decker buses are not allowed specially in the upper floor?
Because the standing may disrupt and tilt the centre of gravity (lowered) Resulting in overturn.
Q122. The oil in a wick rises up due to ...............
capillary action.
Q123. According to work energy theorem what is equal to the work done by a force?
Change in potential energy.
Q124. The three states of matter differs by the ...................................
difference in the magnitude of intermolecular forces.
Q125. What is the useful energy transfer in a radio?
Electrical to sound.
Q126. ...................................colour scatters less.
Red.
Q127. The capillary rise or fall in a capillary tube depends on...................................
surface tension.
Q128. For equilibrium a system must possess .......................potential energy.
minimum.
Q129. The blue colour of the sky is due to the scattering of .....................................wavelength.
shorter.
Q130. Where the weight of an object is at maximum?
on the poles of the earth.
Q131. The purpose of installing transformers in the national grid is.......
to convert DC into AC.
Q132. If the kinetic energy of a body becomes four times of its initial value, Then the new momentum will be ..............
Twice its initial value.
Q133. The quantities that a traveling wave carries with it is................
energy.
Q134. When electrons revolve in the permissible non-radiating orbit, they.........
possess a definite angular momentum.
Q135. The minimum distance required for producing echo is.........
17 mtrs.
Q136. Who suggested the absolute scale of temperature?
Lord Kelvin.
Q137. The functioning of jet aeroplane is based on...............
Newton's III law.
Q138. The mass of object A is 5 kg and B is 8 kg at rest. What is the momentum?
A=B.
Q139. How much of the energy produced by coal burning reaches the consumer as electricity?
one third.
Q140. A wave completes 600 oscillation in 1 minute. What is the frequency of the wave?
10Hz.
Q141. If the velocity of an object is doubled, its kinetic energy will increase by.......
four times.
Q142. In the case of projectile motion, the object should be thrown with.........
initial horizontal velocity.
Q143. The product of frequency and time period is equal to........
1
Q144. An object thrown with a horizontal velocity 42 ms hits the ground in 10 s what is the range?
420m.
Q145. The frequency of a wave is 330Hz and the velocity of sound in air is 330 m/s then what is the wavelength of the wave?
1m.
Q146. The value of Reynold number lies between 0 to 2000, then the flow is called........
Stream lined.
Q147. In which atoms are arranged in a regular, repeated and periodic pattern?
Crystalline.
Q148. The product of mass of the particle and square of its distance is.........
Moment of inertia.
Q149. In a hydro electric power station, the kinetic energy of water is converted Into .......................energy.
electrical.
Q150. Lenz's law is a consequence of the law of conservation of.........
Charge.
Q151. Where should object be placed in simple microscope?
Optic centre and principal focus.
Q152. ............................proposed the equivalence between mechanical and heat energy.
Joule.
Q153. When evaporation take place in a liquid, then its temperatures starts......................
falling.
Q154. The centripetal force required for a car to go round a circular curve depends on its .........
speed and radius of curvature.
Q155. A ray of light traveling in air falls obliquely on the surface of a calm pond, it will
deviate towards normal.
Q156. What is the unit of electric current?
Ampere.
Q157. ..............................is the best conductor of electricity at room temperature.
Silver.
Q158. Between a 60W and 40W bulbs, which one has a higher electrical resistance when in use?
40W.
Q159. Controlled chain reaction take place in ...............
Nuclear Reactors.
Q160. Tungsten is used in electric bulb because of its higher........
melting point
Q161. ............................suggested that electrons are embedded in a positive charged sphere.
Thomson.
Q162. Fleming's right hand rule is also called as........
Generator rule.
Q163. What is the power of an electric lamp, if it draws 20A current when connected to 220V line?
4400W.
Q164. X-rays cannot penetrate through which part of the body?
bones.
Q165. The speed of DC motor can be increased by......................
increasing the number of turns of a coil.
Q166. In AC generator, the e m f varies for every........
half rotation of the coil.
Q167. What is the conventional direction of electric current?
Positive to Negative terminal.
Q168. The emf of a normal dry cell is.......................
1.5V.
Q169. Why is the boiling point of sea water is more than that of pure water?
Because it contains salt and other impurities with different boiling point and together they raise the boiling point of sea water.
Q170. What is the SI unit of heat?
Joule.
Q171. Why is it required to add salt in water while boiling grams?
Addition of salt increases the boiling point and expedites the cooking.
Q172. Ammeter measures.........?
Electric current.
Q173. If the length of the wire is doubled, the resistivity of the wire .........
remains the same.
Q174. Fuse wire in an electric device has to be connected in........
series.
Q175. The nuclear radius is smaller than atomic radius by......................times.
10000
Q176. The other name for Thomson's atom model is........
Plum pudding.
Q177. The charge of electron is........
negative.
Q178. The nuclear volume is found to be ...................................number.
directly proportional to mass.
Q179. What is matter composed of........?
positive and negative charges.
Q180. The mass of a neutron is how many times the mass of an electron?
1838.6.
Q181. The high density of atomic nucleus shows that the nuclear matter is in a what state?
highly compressed.
Q182. The atomic number of an atom is.........
Total number of protons.
Q183. Neutron possesses............................charge.
Neutral.
Q184. A nuclear reaction is always.......................
irreversible.
Q185. Why gamma rays are not deflected?
because they are chargeless.
Q186. What happens when x-ray passes through a gas?
ionizes.
Q187. For which type of atoms, Bohr's postulates are applicable?
Simple atoms.
Q188. Who developed the electronegativity scale?
L.Pauling.
Q189. Why is soft iron used as an electromagnet?
Because it remains magnetic till the current passes through the coil and loses Its magnetism when the current is switched off. (Principle of electric bell).
Q190. The nucleus is assumed to be spherical in shape, this is in accordance with........
Liquid drop model.
Q191. In a nuclear reaction, the number of fissions takes place at each successive stage goes inducing in......................
Arithmetic progression.
Q192. The minimum mass of the nuclear fuel below which the chain reaction stops is..
Critical mass.
Q193. In a nuclear reactor, the excess neutrons are absorbed with the help of........
control rod.
Q194. When an atom bomb explodes a large amount of........
radio active radiations and neutrons are produced and released.
Q195. The minimum mass of the nuclear material below which the chain reaction stops is.......................
Critical mass.
Q196. .............................radiation has no charge and no mass and travels with the velocity of light.
Photon.
Q197. Which fuel is used in fast breeder test reactors?
Mixture of carbides of uranium and plutonium.
Q198. Who was the first chairman of the atomic energy commission?
Dr.Homi J.Bhabha.
Q199. An electric short circuit does not occur when the...............
neutral wire comes in contact with the earth wire.
Q200. Who proposed the "quantum theory"?
Max Planck.
Q201. When the number of turns in a current carrying circular coil increases, The magnetic field developed.........
increases.
Q202. A dynamo is used to produce..............................current using ..................................... .
direct, a commutator.
Q203. Who experimentally studied the natural radio activity?
Rutherford.
Q204. The transmutation of non radioactive into radioactive element is called........
Artificial radioactivity.
Q205. How much potential is required to produce x-rays?
100000 v.
Q206. ..............................force is the weakest among the basic forces?
gravitational.
Q207. Which radiation has maximum ionizing power?
Alpha.
Q208. Which isotope is used in self luminous paints and post makers?
Radio prometrium.
Q209. ......................is the unit of activity.
Becqueral.
Q210. Name the process in which two light nuclear combined together to form Heavy nucleus?
Nuclear Fusion.
Q211. Why does ink leak out of a partially filled pen when in higher altitude?
Because the pressure of air acting on the tube of the pen is greater than the pressure of air outside.
Q212. Who first detected radio waves coming from space?
Karl G. Jansky, USA.
Q213. Which material is coated on the screen in Roentgen's experiment?
Barium platinum cyanide.
Q214. What is the mass number of an element containing 20 neutrons and its Atomic number is 12?
32
Q215. How much energy is released during nuclear fusion?
17.6 Mev.
Q216. The magnitude of the induced emf is equal to the rate of change of........
Flux linked with the coil.
Q217. The phenomenon of electromagnetic induction was discovered by.........
Michael Faraday.
Q218. The force on a charged particle moving in a magnetic field is maximum. What is the angle between the direction of motion and field?
90 degree.
Q219. In a transformer due to electromagnetic induction the varying flux sets up on emf in the.........
Secondary coil.
Q220. The magnitude of mechanical force acting on a current carrying conductor is proportional to...............
Both current and length.
Q221. One horse power is equal to .........
764w.
Q222. If the transformer ratio is KC1, then the transformer is a.....................................
Step up as well as step down.
Q223. The varying magnetic flux in the primary coil due to alternating current links.......
both primary and secondary coils.
Q224. A permanent magnet can be demagnetized by.........
placing it inside a solenoid carrying alternating current.
Q225. Why do some liquids burn while others do not?
A liquid burns if its molecules can combine with oxygen of the air with the Production of heat. Hence, oil burns but water does not.
Q226. Who gave the concept of the first integrated circuit?
Jack S.Kilby, USA.
Q227. Oil and water do not mix. Why?
i) Molecules of oil are bigger than that of water and therefore do not mix easily. ii) Molecules of water are polar, that, is, they have opposite charges at two ends, whereas oil molecules do not; as a consequence they tend to stay away from water molecules.
Q228. Current carrying conductor when in a magnetic field experience a force due to...............
the interaction between magnetic fields.
Q229. When a steel rod is used in the place of soft iron rod in an electric bell.........
it does not ring continuously.
Q230. .............................rule is used in DC generator.
Fleming's right hand rule.
Q231. A magnet is pushed into a coil of wire. What happens if the magnet is then Pulled out at higher speed?
A bigger current is induced in the same direction.
Q232. What is the turns ratio in a step up transformer?
>1.
Q233. ..........................................is used to for changing the AC voltage into different voltages.
Transformer.
Q234. The work done in moving a charge of 5C across the potential difference of 13V is............................
65J.
Q235. The commutator or slip ring is used for ........
Changing the direction of the current.
Q236. Electrical current will stop flowing when the potential difference is........
Zero.
Q237. The simplest way of maintaining a potential difference between the two ends of a conductor is..............
to connect it to a battery or dry cell.
Q238. Commercial unit of electrical energy is.........
Kilowatt-hour.
Q239. When the current flowing through a resistance increases four times, the heat developed will increase by ..............
16 times.
Q240. If a magnet is cut into two pieces of equal length.............................
both piece will behave as complete magnets.
Q241. In which scattering the scattered wave length is equal to the incident Wavelength?
Rayleigh distribution.
Q242. The magnitude of force on current carrying conductor is the highest when The direction of current is.....................
Right angle to the direction of magnetic field.
Q243. The process of doping is associated with...............
semi conductors.
Q244. ..............................converts mechanical energy into electrical energy.
Dynamo.
Q245. In Fleming's left hand rule, which finger indicates direction of force?
Thumb.
Q246. How will you convert galvano meter into ammeter?
Low resistance in parallel.
Q247. Galvanometer works on the principle of........
Fleming's left hand rule.
Q248. Magnetic induction is a ................
Vector.
Q249. Whose theory concluded that atom cannot be subdivided?
Dalton.
Q250. How fast a man of mass of 100 kg to run so that his kinetic energy is 800J?
4 m/s.
Q251. .................prevents excess flow of current through electrical appliances.
Fuse.
Q252. A fixed resistor is called.........?
Resistor.
Q253. The resistivity of a material is independent of the..............
shape and size of the conductor.
Q254. What is the direction of mechanical force produced by a current carrying Conductor?
perpendicular to both.
Q255. Ampere second is the unit of.........
charge.
Q256. The electrical resistance of a conductor depends on ........
its length.
Q257. Magnetic field does not interact with.........
Electric charges at rest.
Q258. What is a shunt?
A low resistance in parallel.
Q259. When the length of the wire is halved, the resistance gets.........
halved.
Q260. An electron enters a uniform magnetic field along X axis perpendicularly With a velocity along Y axis. In what direction will it deflect?
Z Axis.
Q261. Energy produced from water is called........
hydro-energy.
Q262. Who devised the first calculating machine?
Pascal.
Q263. Why does a solid chunk of iron sink in water but float in mercury?
Because the density of iron is more than that of water but less than mercury.
Q264. Who produced the first alcohol thermo meter?
Marconi.
Q265. Coal is a .................................................energy.
non-renewable.
Q266. Geothermal energy is feasible in regions that .....................
area over hot spots in the crust.
Q267. The time period of a simple pendulum does not depend on........
Mass of the bob.
Q268. ...................................is a scalar quantity.
Magnetic flux.
Q269. In DC motor, the direction of force is given by........
Flemming's left hand rule.
Q270. The strength of magnetic field produced by a current carrying solenoid does not depend upon...............
direction of current.
Q271. ....................................converts electrical into mechanical energy.
Motor.
Q272. When a charged particle enters a uniform magnetic field its kinetic energy........
remain constant.
Q273. A current is flowing in a curricular loop of wire in clockwise direction. The Magnetic field at the centre of the wire is...................................................
directed downward.
Q274. The electric current is due to drift of free electrons in..............
Metalic conductors.
Q275. When current passes through a straight conductor, the magnetic field lines around it are in the form of ...................................with the conductor as the centre.
concentric circles.
Q276. The electromagnetic induction is a phenomenon in which...........................................is developed from change of .............................
electricity, magnetic field.
Q277. The Ohm's law deals with ..............
current and potential difference.
Q278. ......................is used for measuring the potential difference.
Voltmeter.
Q279. Why do stars twinkle?
The light from a star reaches us after refraction as it passes through various layers of air. When the light passes through the earth's atmosphere, it is made to flicker by the hot and cold ripples of air and it appears as if the stars are twinkling.
Q280. Who is known for this mathematical theory of electricity?
J.J.Thomson.
Q281. Who is known as the father of photography?
S.H.Sharpe.
Q282. What happens when ebonite rod is rubbed with fur?
Electrons move from the fur to the ebonite rod.
Q283. With an increase of temperature, in a metallic conductor, the conductivity ...................................and resistivity ........................................................ .
decreases, increases.
Q284. Why Nichrome is preferred for making heating elements?
High resistivity.
Q285. If a convex lens of focal length 15cm forms an image at 35cm, the distance of the object is...............
-- 26.25cm.
Q286. The magnification produced by a mirror is 2. The image formed by the Mirror is.................................... .
Virtual and magnified.
Q287. The ratio of change in dimension to the original dimension is known as............................
Strain.
Q288. What makes the ink to stick to paper while writing?
Force of adhesion.
Q289. When an insect walks on the surface of water, the force of surface tension acts..............
along an inclined direction.
Q290. The free surface of liquid behave like a .........
plastic surface.
Q291. The particular temperature at which the surface tension of the liquid become Zero is called.......................
Critical temperature.
Q292. What substance is used to pour around the ships to calm the sea waves?
oil.
Q293. The mercury.......................................... ............................. when a capillary tube is dipped in mercury.
Depresses below.
Q294. Due to the interatomic force, the atoms in solids ......................................................... .
can move freely.
Q295. The rate at which a fluid flows through a pipe depends on............................................
Pressure difference between the ends.
Q296. .....................................force restricts the reactive motion of different layers in liquids.
Frictional.
Q297. ...................................is used for measuring atmospheric pressure.
Barometer.
Q298. When an external force of sufficient magnitude is applied on a body of some Mass, the body acquires...................................
Inertia.
Q299. In solids, the interatomic force is............................
weak.
Q300. Steel wires are used to suspend heavy loads because they have.....................................
strong cohesive force.
Q301. The molecule which is well inside the liquid is attracted.......................
In all directions by the neighbouring molecules.
Q302. Surface tension of the oil is ..............................than that of water.
lesser.
Q303. Rain drops fall due to gravity when the drops undergo ................ velocity.
Terminal.
Q304. ..............................is dual in nature.
Light.
Q305. ....................................theory supports Raman Effect.
Quantum.
Q306. .....................................is not a vector quantity.
Density.
Q307. ....................................is a vector quantity.
Displacement.
Q308. At a height of 12800 Km from the centre of the earth, what is the value of g?
Double the value at earth's surface.
Q309. .............................is called the rate of change in velocity.
Acceleration.
Q310. A stone released from a height, reaches the ground in 2 seconds. What is the height from which it was released?
19.6 mtrs.
Q311. Who measured air pressure in the atomosphere?
Galileo.
Q312. Who devised the system of Seismography?
Robert Mallet.
Q313. Why cooking is quicker in a pressure cooker?
As the pressure inside the cooker increases, the boiling point of water is raised, hence the cooking process is quicker.
Q314. Who conducted the experiment that produced vacuum for the first time?
Blaise Pascal.
Q315. Uniform circular motion is a ...................................................motion.
accelerated.
Q316. What is the disadvantage of solar cells?
They do not produce electricity at night.
Q317. Why coal, oil and natural gas are considered as non-renewable energy?
Because, they cannot be replaced except over very very long period of time.
Q318. Uranium and Plutonium are used as nuclear fuels because they are........
radioactive.
Q319. What is the advantage of nuclear fuels?
They do not produce green house gases.
Q320. Sulphur dioxide causes....................................
harm to the ozone layer.
Q321. Velocity of sound is maximum in............................
copper.
Q322. ............................................barometer essentially consists of a thin metal box Exhauster of air?
Aneroid.
Q323. Moment of inertia does not depend on............................
angular velocity.
Q324. When electrons revolve in the permissible non-radiating orbit, they....................................
possess a definite angular momentum.
Q325. The moment of inertia of a body comes into play in...................................
Rotational motion.
Q326. When the electrons are moving in the discrete and permitted orbit they..............
do not radiate energy.
Q327. Thermal power plants use .....................................to produce electricity.
Coal, Oil.
Q328. ..............................force always produces retardation.
Frictional.
Q329. When a force is exerted on an object, changes will occur in its...............
state, position and shape.
Q330. What happens when an objects gets an acceleration?
A force acts on it.
Q331. What will be the acceleration, if no external force acts on an object?
Zero.
Q332. The frequency of bats is........
above 20000 Hz.
Q333. ..............................waves are produced when the strings of violin is plucked.
Transverse.
Q334. Why do we see lightning first and then hear the thunder?
Because speed of light is more than that of sound.
Q335. When wood burns, it crackles. Why?
Wood contains a complex mixture of gases and tar forming vapours trapped near the surface. These gases and tar vapours excape making a crackling sound.
Q336. Who discovered electricity in lightning?
Benjamin Franklin.
Q337. A lamp consumes 1000J of electrical energy in 10s. What is its power?
100W.
Q338. The other name for Nm is.....................
Joule.
Q339. Propagation of wave transfers .......................
energy.
Q340. .............................waves does not require medium to its propagation.
Light.
Q341. When the string of sitar is plucked what waves are produced?
Transverse and longitudinal waves in air.
Q342. The distance moved in completing one oscillation is called...............
wavelength.
Q343. The horizontal distance between the point of projection and the hitting point on the ground is..............................
range of projectile.
Q344. The object which moves in a straight line comes under.......................motion.
linear.
Q345. Bernoulli's theorem is a consequence of the law of conservation of.........
energy.
Q346. A skydiver with an unopened parachute is an example for.......................
freely falling body.
Q347. The angular acceleration is ............................
rate of change of angular velocity.
Q348. The moment of linear momentum of the particle is......................
Angular momentlum.
Q349. The disadvantage of using fossil fuel is, it ...................................
causes green house effect.
Q350. What force provides the centripetal force between the tyre and ground of a car that is taking a curve?
Frictional.
Q351. Fossil fuels are formed in about .....................................years.
100 million.
Q352. Gobar gas plant functions on the principle of............................
Anaerobic degradation of biomass.
Q353. Pressure is defined as.........
Force / area.
Q354. A lens may be considered to be made up of.............................
Prisms.
Q355. .............................contains the sources of energy by the fusion of helium nuclei.
Sun.
Q356. The velocity of light in a diamond is 2/3 of its velocity in air. What will be its refractive index?
1.5
Q357. A feather, a wooden ball, and a steel ball fall simultaneously in a vacuum. Which one of these fall faster?
All will fall at the same speed in a vacuum because there will be no air resistance and earth's gravity will exert a similar gravitational pull on all.
Q358. The blue colour of the clear sky is due to?
Refraction of light where violet and blue colors gets scattered by the presence of particles in the atmosphere.
Q359. The refractive index of glass depends on the ...................................
size of the glass slab.
Q360. Evaporation occurs at the .............................of the liquid.
surface.
Q361. The loss of time clocks due to heat is maintained by.............................
Bimetallic pendulum.
Q362. Liquids vaporizing fast is called as the ...................................
Boiling.
Q363. .............................is the universal coolant used in radiators.
Water.
Q364. The volatile liquid used in refrigerator is............................
Freon.
Q365. 1HP (horse power) equals to..............
746 W.
Q366. The colour that is obtained by mixing magenta, yellow and cyan is......................
white.
Q367. ...................................liquids evaporates easily.
Volatile.
Q368. The acceleration of an object on free fall is independent of its............................
mass.
Q369. The principle of centrifugal force is applied to the machines known as........
centrifuges.
Q370. Light is used in measuring large distance called............................
Light Year.
Q371. The air resistance on a falling body depends on.........
the shape, size and speed of the fall of the body.
Q372. Why an explosion on the moon cannot be heard?
Because sound waves required material medium for propagation which is absent on the moon.
Q373. When an object falls freely, the kinetic energy of the object.....................
increases.
Q374. Which effect of electric current is used in gold plating of silver jewellery?
Chemical.
Q375. ....................................is used to test whether a subject is charged or not.
Electroscope.
Q376. When a car is around a curve, the centripetal force is directed..............
toward the centre of the circular curve.
Q377. What is the unit of frequency?
Hertz.
Q378. When a man fires a gun, he is pushed back slightly. How?
As the bullet leaves the nozzle of the gun's barrel with momentum in a forward direction as per Newton's third law of motion, the object of the bullet imparts an equal momentum in a backward direction.
Q379. Two forces acting at right angles, having the same effects of a single force, it is called as.......................
Components.
Q380. The energy possessed by a body due to its position or configuration is.....................
Potential.
Q381. Energy can neither be created nor be destroyed ? this statement belongs to........
The Law of conservation of Energy.
Q382. Kinetic energy of a body in motion equals the product of half of its mass and the square of its ...................................
velocity.
Q383. Modified Barometers, used to measure the height above the sea level is called..
Altimeter.
Q384. The equilibrium obtained by a funnel lying horizontally on its side at rest on a table is............................
Neutral.
Q385. How many kinds of equilibrium are there?
Fundamentally three .. Stable, Unstable and Neutral.
Q386. The resistance offered by an object to an applied force is referred to as................
Inertia.
Q387. Vaporization point and .....................point have the same numerical value.
Liquification.
Q388. ..............................has the highest specific heat capacity.
Water.
Q389. Momentum is defined as..............................
Mass X Velocity.
Q390. A cart is pulled along the road for a distance of 5m. If the average frictional Force is 47N, then what is the work done?
235 J.
Q391. The amount of heat required to change a unit mass of solid into liquid without changing its temperature is ......................
Fusion.
Q392. When an object is placed between the pole and the focus point of a concave mirror, the image formed will be.........
behind the mirror.
Q393. The focal length of eye lens is more when eye lens become ...............
thin.
Q394. The rate of change ............................is due to force applied.
momentum.
Q395. What happens when white light falls on non-parallel surfaces of a glass block?
Dispersion.
Q396. The sky appear dark instead of blue to an astronaut, because of .........
absence of scattering.
Q397. ............................material is used to absorb the heat produced in the chain reaction.
Coolant.
Q398. When two plane mirrors are placed perpendicular to each, the number of images produced will be..............
Three.
Q399. A well cut diamond appears bright because of .....................
Total internal reflection.
Q400. In the course of refraction of light, the ................................... does not change.
frequency.
Q401. When monochromatic light passes from denser to a rarer medium, the velocity...................................
increases.
Q402. A plane mirror can form an inverted image, when the object is placed.......................
on top of the mirror.
Q403. The most common characteristic of X, Gamma, IR, UV rays and visible Light is that........
all of them are harmful to the health of living organisms.
Q404. In order to see full length image, a person requires a plane mirror, which is ..............................of his own height.
half.
Q405. .....................lens is used for reading purposes.
Convex.
Q406. The maximum kinetic energy of photoelectrons depends on................
frequency of light.
Q407. Rays of light traveling from a rarer medium to a denser medium will..............
Bend towards the normal.
Q408. What is the position of the image when an object is placed at infinity in front of a concave lens?
Principal focus on the same side.
Q409. ................colour deviates the most while passing through a prism.
Blue.
Q410. The branch of physics which deals with the measurement of light is............................
photometry.
Q411. Why does a body weigh slightly more at the poles than at the equator?
The gravitational pull of the earth is more at the poles because the poles being Nearer to the centre, the weight of a body is greater at this point.
Q412. What energy transformation takes place in a microphone?
Sound into electrical energy.
Q413. Why is it easier to roll a barrel than to pull it?
Because the rolling force of friction is less than the dynamic force of sliding friction.
Q414. A copper plate is heated to 200 degree C. It cools by emitting ..............
IR rays.
Q415. In refraction through a glass slab, the...............ray and ...............ray are parallel to each other.
Incident, emergent.
Q416. The shortest distance between two points on a plane is..............................
straight line.
Q417. What is the apparent depth of the glass slab when an object seen through 10cm thick glass slab appears to be raised by 3cm?
7 cm.
Q418. For a given prism, the angle of deviation of each colour is independent of........
the refractive index of the prism.
Q419. The power of lens is ............................
inversely proportional to focal length.
Q420. IR are used for......................
Treatment of arthritis.
Q421. An hypermetropic eye cannot see objects at................
20 cm.
Q422. Microwaves are generated by the electronic device.............................
Magnetron.
Q423. .............................waves are used for radar communication.
Micro.
Q424. Cell phones use...................................
Radio waves.
Q425. Radio waves are used in .....................................
telecommunication system.
Q426. Persons working in Nuclear power station must wear aprons made of......................
Lead.
Q427. IR and UV rays, both obey..............
laws of reflection and refraction.
Q428. ............................is used for detecting IR rays.
Thermopile.
Q429. Light consists of bundles of energy called photons. Who said this?
Einstein.
Q430. UV rays are used for purifying.................................................
drinking water.
Q431. ..............................effect gives stoke's line.
Raman.
Q432. ...................................depletes the ozone layer.
Chlorofluorocarbons.
Q433. IR rays scattered well because of their................
longer wavelength.
Q434. When an object absorbs all the colours of white light the object appears........
Black.
Q435. When intensity of the incident radiation increases, what happens to the potoelectric current?
Increases.
Q436. The maximum kinetic energy of photo electrons is independent of.........
intensity.
Q437. When an object reflects all the colours of white light, how does the object Appears?
white.
Q438. During interference, light behaves like.....................
waves.
Q439. The purpose of the transformer is to .....................................
convert low voltage into higher voltage and vice versa.
Q440. Ice wrapped in a blanket or saw dust does not melt quickly. Why?
Because, wool and wood are bad conductors of heat and do not allow the heat to react easily with ice.
Q441. The twinkling of starts is due to....................................
refractive index fluctuation in the atmosphere.
Q442. The cause of the green house effect is due to..............................
increase in temperature of the earth.
Q443. The speed of electro magnetic waves is independent of...................................
intensity.
Q444. ...................................is used in the detection of UV rays.
Quinine Sulphate.
Q445. The spectral lines having higher frequencies than that of incident light are called.........
Antistoke lines.
Q446. The value of acceleration due to gravity is.....................
different at different places.
Q447. A light ray traveling from a denser medium to a rarer medium is transmitted only at ......................
critical angle.
Q448. Two bulbs of 100 W and 200 W have been connected in parallel with 220V AC supply. Which bulb has more current to flow through?
200W.
Q449. A plane mirror reflects a beam of light to form a real image. The incident beam is................
convergent.
Q450. What happens when a monochromatic beam of light passes from denser to rarer medium?
velocity increases.
Q451. What does "Angstrom" measure?
Length of light waves.
Q452. Why do we perspire on a hot day?
When the body temperature rises, the sweat glands of the body are stimulated to secrete perspiration. It is nature's phenomenon to keep the body cool. during the process of evaporation of sweat some body heat is taken away thus giving a sense of coolness.
Q453. Which instrument is used for measuring small currents?
Galvanometer.
Q454. Why do we perspire before rains?
Before the rain falls, the atmosphere gets saturated with water vapours, as a result, the process of evaporation of sweat is delayed.
Q455. .....................................lens is used to see the lines on the palm of a human clearly.
convex.
Q456. The rod in the dry cell, which act as the positive terminal, is made of........
Carbon.
Q457. If two stones of different masses are dropped at the same time from a height both will reach the ground at ............................
the same time.
Q458. A ray emerging from a point on the object, passing through the centre of Curvature c, strikes the mirror normally. What is the angle of incidence?
0 degree.
Q459. A concave mirror of focal length 20cm is dipped in a liquid of refractive Index 1.67, then the focal length is ..............cm.
20
Q460. A straight wire of length 0.4 meter and carrying a current of 1.5n is Placed perpendicular in uniform magnetic field of induction 3 tesla. What is the force on the wire?
1.8N.
Q461. When the critical angle for a medium is 60 degree, what will be its refractive Index?
1.15.
Q462. ............................lens has thinner edges and thicker centre.
Concave.
Q463. The focal length of a lens is 30cm., the given lens is.............................
Diverging.
Q464. The image formed by a concave mirror is observed to virtual, erect and larger than the object. Where should be the position of the object?
between the pole and principal focus.
Q465. When is it possible to observe total internal reflection?
A ray travels from glass into water.
Q466. The refractive index of glass with respect to air is 1.85. What is the Refractive index of air with respect to glass?
0.54.
Q467. A plane mirror produces a reversal effect, where left side of the object Seems to be right. What is this property?
Lateral inversion.
Q468. The number of images formed when an object is placed in front of a thick glass mirror is.......................
multiple.
Q469. The electromagnetic waves propagate in a direction..............................
perpendicular to electric and magnetic field.
Q470. Why one cannot see through fog?
Light is scattered by the droplets in a fog.
Q471. What remains constant when objects at different distances are seen by the eye?
The image distance from the eye lens.
Q472. Electromagnetic waves do not require material medium to propagate. Right or Wrong?
Right.
Q473. The minimum energy required to remove an electron is.......................
Work function.
Q474. Why does ice float on water but sink in alcohol?
Because ice is lighter than water, ice floats on it. However, ice is heavier than Alcohol and therefore it sinks in alcohol.
Q475. Photo electric effect was discovered by.......................
Hallwachs.
Q476. Electromagnetic waves satisfies all the phenomena of............................
Light.
Q477. Electromagnetic waves are produced by.........
Oscillating electric charges.
Q478. 550KHz -- 1600JHz is the frequency range of.......................
AM band.
Q479. The power of the lens to correct the vision of a person who cannot see Objects beyond 50cm is..............
--2D.
Q480. The amount of ...................................in the old articles describes its age.
Radio Carbon.
Q481. ............................rays are used to find structure of atoms.
UV.
Q482. The wave length of wave having frequency of 1200KHz is............................
250m.
Q483. Microwaves are generated by .........
Magnetron and Klystron.
Q484. The value of wave length of electro magnetic wave produced by hertz is...............
6 m.
Q485. In an electromagnetic wave, power is transmitted ................
perpendicular to both fields.
Q486. Telephone and Radar use...................................
microwaves.
Q487. The ionizing power of gamma rays is ...............
very low.
Q488. What will happen to the mass number when gamma particle is emitted?
Unchanged.
Q489. Radio Iodine is used as a ......................
Tracer.
Q490. Medical, Security and Industries use ..............rays.
X.
Q491. Latent heat of vaporization of water boiling under normal pressure is......................
540 cal/g.
Q492. Which lens and what focal length is used by a person having power of 2.50D?
Convex, 40.
Q493. Tyndall effect is not a consequence of............................
Total Internal Reflection.
Q494. The major disadvantage of the solar cells is that its........
efficiency is low.
Q495. ............................rays are emitted by an electric heater.
IR.
Q496. The phenomenon of electromagnetic induction is the process of.........
producing induced current.
Q497. The frequency of AC mains used in India is...............
50Hz.
Q498. The Fusion reaction occurs at.......................
High temperature.
Q499. .............................mirror is used in the construction of reflecting periscope.
Plane.
Q500. Which instrument is used for precise measurement of refractive indices?
Spectrometer.
Q501. Why does a thermometer kept in boiling water show no change in reading?
The boiling point of water is 100 degreeC. Once water starts boiling at this temperature, thermometer records no change in temperature. The quantity of heat supplied is being utilized as latent heat of evaporation to convert the water at boiling point into vapour.
Q502. Who discovered the law of attraction and repulsion between electric charges?
Couloumb.
Q503. The lightning conductor used for protecting buildings from lightning is made of?
copper.
Q504. The refractive index is more for..............
Shorter wavelength.
Q505. What happens to the speed of light when it is refracted from water into air?
Speed increases.
Q506. The image formed by a concave lens will always be............................
smaller than the size of the object.
Q507. The mirror formula is valid for..............................
all spherical mirrors.
Q508. .....................colour deviates least in the formation of spectrum by a prism.
Red.
Q509. The process of a solid changing to liquid after heating is called.......................
melting.
Q510. When is a prism said to be in minimum deviation?
i = 0.
Q511. The water drops acts like a ............................lens.
Convex.
Q512. A plane mirror of height 4.5 feet is used to see the entire image of a pole. Therefore, the height of the pole will be.........
9 feet.
Q513. .............................mirror is used in the shaving glass.
Concave.
Q514. The nature of image formed by a concave lens is.....................and .......................
Virtual, erect.
Q515. Why does a water filled corked bottle burst when it is left out on a frosty night?
Due to low temperature the water inside the bottle freezes. On freezing it expands, thereby its volume increases and pressure is exerted on the walls.
Q516. A ray of light appearing to meet the principal focus of concave lens, after refraction...........................................
Emerge parallel to the principal axis.
Q517. When light goes from rarer to denser medium...............
Angle of incidence > Angle of refraction.
Q518. The real inverted and highly diminished image if formed at focus of lens then........
Object is at infinity and lens is convex.
Q519. The refraction takes place in the lens because the refractive index of glass is more/less/equal to the air. Is this statement correct?
No. Refraction does not depend on refractive index.
Q520. A ray of light passing through the focus of the mirror, after reflection........
becomes parallel to the principal axis.
Q521. Where should an object be placed in front of a convex lens to get a real Image of the object?
at twice the focal length.
Q522. The focal length of concave lens is always........
negative.
Q523. The SI unit of power of lens is.......................
Dioptre.
Q524. The sound waves which cannot be heard by a human ear are called?
Infrasonic and Ultrasonic.
Q525. Why is a small gap left at the joint between two rails?
To permit expansion of rails due to heat generated by friction of the moving train.
Q526. ..............................mirror forms a diminished and virtual images.
Convex.
Q527. The bending of light ray due to change in its speed is.....................
Refraction.
Q528. Parallel light rays appear to pass through ..............after refraction from concave lens.
focus.
Q529. ...................................lens is used to concentrate the sunlight over a small part of paper which makes it burn.
convex.
Q530. Light takes a ---------path.
straight.
Q531. The principle used in multiple reflections is............................
Kaleidoscope.
Q532. A force of 5N acts on a mass of 1 Kg which acquire 40 m/s. What is the time for which the force acts?
8 Sec.
Q533. Light propagates easily through...............
transparent.
Q534. A sound wave has a frequency of 1000Hz and a wavelength of 32 cm. What is the velocity of the sound wave?
320 m/s.
Q535. The law of conservation of momentum states that the momentum of a system.......
can be changed by external force.
Q536. Glass does not allow which rays to pass through?
IR.
Q537. The splitting of colours is called............................
Dispersion.
Q538. .....................................mirror is used as a reflector in street lights.
Convex.
Q539. ............................colour is strongly scattered by the molelcules of air.
Blue.
Q540. A long vertical rod placed at 60 cm in front of a concave mirror gives an image at the same position. What is the focal length of the ?
30cm.
Q541. The colour of the sky when it is seen from moon's surface will be........
Black.
Q542. The value of refractive index of a medium depends on..............................
nature of the medium and frequency.
Q543. IR red was detected by........
William Herschel.
Q544. The image formed by a concave mirror ..................... ...................... ............................ .............. when an Object is placed at the focus of the mirror.
will not be virtual.
Q545. To get a real inverted and diminished image between F and C, where should the Object be placed?
Beyond C.
Q546. When an object of 3 cm height is placed in front of a mirror, the magnification Produced by the mirror is 8, what will be the size of the image formed?
24 cm.
Q547. ......................will be the colour of the sunlight when it is scattered by the dust particles.
white.
Q548. The angle between electric and magnetic fields of an EM wave is.....................
90 degree.
Q549. A long vertical pin placed 50cm in front of a concave mirror gives an image at the same position. What is the focal length of the mirror?
25 cm.
Q550. ..............................is the emission source for microwaves in a typical microwave ovens.
Magnetron.
Q551. A telescope has focal length of objective and eye piece as 200 cm and 5 cm Respectively. What is the magnification of telescope?
40 .
Q552. .............................colour can be obtained when a primary and secondary colour are mixed.
White.
Q553. ..............................is a force carrying particle.
Photon.
Q554. Bodies that radiate light are known as............................
Luminous.
Q555. Magnetic lines of force travel from .................................... ......... ............................outside the magnet.
North to South.
Q556. The distance between two consecutive crests of a wave is called................
wavelength.
Q557. The phenomenon of an unmagnetized magnetic substance behaves like a magnet due to the mere presence of another magnet is known as................
Magnetic induction.
Q558. ....................................beam is the one whose remains the same distance apart.
Parallel.
Q559. The direction of the conventional current in a diode is..............................
Plate to cathode.
Q560. A cyclist has to use more force at the start than when the cycle is in motion. Why?
Momentum has to be produced to set a cycle in motion requiring more force. But, once momentum has been obtained, smaller force is enough to keep the momentum going.
Q561. The light of which colour has the longest wavelength?
Red.
Q562. The imaginary vertical plane passing through the magnet of a freely suspended bar magnet is...................................
Magnetic Meridian.
Q563. The number of sound vibrations per second is known as..............
Frequency.
Q564. ..............................mirrors are used to concentrate sunlight to generate high temperature in solar furnaces.
Concave.
Q565. The distance between the magnetic north and south pole is called.......................
Effective length.
Q566. Non-luminous become visible when they..............................light.
reflect.
Q567. When the water vapour in the atmosphere condenses and clouds are formed, these clouds contain large amount of .......................changes.
Static electric.
Q568. Why copper wires are not used to make elements in electric heaters?
Copper melts at 1083 degreeC and forms a black powder on reacting with atmospheric oxygen. For heater element a metal should have more resistance to produce heat.
Q569. What is the unit to measure supersonic speed?
Mac.
Q570. Electrons that move very easily from one atom to another are called............................. electrons.
Free.
Q571. Lightning occurs before or after thunder.....
Before -- because light travels faster.
Q572. When a divergent beam of light is incident on a plane mirror, it is reflected back as a ...................................beam.
divergent.
Q573. Most of the magnetic power appears to be concentrated at certain points. They are called......................?
Poles.
Q574. The direction of the flow of heat depends upon............................
Temperature difference.
Q575. A proton has the same mass as.....................
Neutron.
Q576. The frequency of tuning fork that vibrates 3750 times in 5s is.........
1250Hz.
Q577. When a coil spring is compressed, the elastic potential energy.....................
increases.
Q578. Why is water or mercury always round when dropped on a clear glass?
The surface of a liquid is the seat of a special force as a result of which Molecules on the surface are bound together to form something like a stretched membrane. They tend to compress the molelcules below the smallest possible volume which causes the drop to take a round shape as for a given mass sphere has minimum volume.
Q579. What is the unit of force?
Newton.
Q580. The maximum displacement of a vibrating body from its mean position is called......................
wavelength.
Q581. What is the angle between displacement and the force applied, when the work done is maximum?
0 degree.
Q582. Why does a balloon filled with Hydrogen rise in the air?
Its weight is less than the weight of the air displaced by it. In balloons Normally hydrogen is filled which is lighter than air.
Q583. ......................property of a body oppose the flow of electric charge through it.
Resistance.
Q584. Where negatively and positively charged ions free to move constitute current?
In both electrolytes and gases.
Q585. Resistance offered by the conductors does not depend on ............................ ............................ of the conductor.
Surface area.
Q586. When more than one resistors are in series, which quantity remains constant?
Current.
Q587. ..........................................water does not conduct electricity.
Distilled.
Q588. If a microwave oven has the rating of 1100 W, 220 V marked on it. What should be minimum rating of the fuse put by the electrician in the part of the circuit?
10
Q589. The density of nucleus is very high. This shows that nuclear matter is in.........
Highly compressed state.
Q590. Radio isotope promethium is used for............................
Illuminating.
Q591. The total mass of the fissionable material in an uncontrolled chain reaction is.......
Greater than its critical mass.
Q592. Which one determines the fission reaction whether it is controlled or uncontrolled?
Reproduction factor.
Q593. .............................slightly heavier than proton.
Neutron.
Q594. Which model is referred to J J Thomson's atom model?
Alpha particle model.
Q595. The total number of nucleons in the nucleus of the atom is called.........
Mass number.
Q596. For an uncontrolled chain reaction, the reproduction factors is.......................
Greater than one.
Q597. ....................................elements exhibit the phenomenon of natural radioactivity.
Heavy.
Q598. The weakest force that dominates the Universe is.........
Gravitational.
Q599. X-rays are..............
photons of high energy.
Q600. Which non-metal conducts electricity?
Carbon.
Q601. The rays coming out of Uranium sample affects..............
Photographic plates.
Q602. The penetrating power of x-rays are ..............................
very high.
Q603. ...................................is used to heat the tungsten filament in Coolidge tube.
Low tension battery.
Q604. The jumping of electron from higher to lower energy state determines what?
Frequency of radiation.
Q605. X-rays are electromagnetic waves of............................
very short wavelength.
Q606. In Coolidge tube, anode tungsten is embedded in....................................
copper block.
Q607. Which alloy is used for making permanent magnet?
Steel.
Q608. Why does smoke curl up in the air?
Smoke contains hot gases which, being lighter in weight, follow a curved path Because of the eddy currents that are set up in the air.
Q609. In a Coolidge tube, the high potential is applied to.........
secondary of an induction coil.
Q610. X rays ionize the gas through which they pass. True or False?
True.
Q611. Bohr atom model could not explain.....................
fine structure of special lines.
Q612. Which parameter determines fission reaction whether controlled or Uncontrolled?
Reproduction factor.
Q613. Nuclear Fission Reaction was discovered by....................................
Otto Hahn and Strassman.
Q614. In nuclear reaction, the liberated neutrons escapes from the reactor due to........
very small size of the fuel.
Q615. The principle used in atom bomb is .......................
Uncontrolled chain reaction.
Q616. In the controlled chain reaction, the number of fissions produced per second is.......
constant.
Q617. Which part of the nuclear reactor absorbs the heat energy released?
Coolants.
Q618. Moderators are used to ...................................
speed up the neutrons.
Q619. To start the chain reaction ..................................................particle is used.
slow moving neutrons.
Q620. The heat absorbed by the coolant is transferred to the water in the.......................
Heat exchanger.
Q621. What are the rays released during the explosion of atom bomb?
Visible rays, UV and X rays.
Q622. To prevent the leakage of nuclear radiation, what is provided with the nuclear reactor?
Radiation Shield.
Q623. SI unit of heat is...............
Calorie.
Q624. Who invented the pendulum of clock?
Galileo.
Q625. Who invented the cellophane?
J.Brander Perger.
Q626. What is a Femto Second?
A Femto Second .... millionth of a billionth of a second.
Q627. Why do we lean forward while climbing a hill?
In order to keep the vertical line passing through our centre of gravity always between our feet to attain balance or stability.
Q628. The reactor which produce their own fuel during their operation is called........
Fast Breeder.
Q629. The order of temperature when atom bomb explodes is..............................
Millions of degrees of celcius.
Q630. Reactors which convert nuclear energy into electronic power are called.....................
Power reactors.
Q631. The important factor for the sustained nuclear chain reaction stops is called........
Size of the fuel.
Q632. Which one is the antiparticle of electron?
Positron.
Q633. A magnet cannot be demagnetized by.........
Placing the unlike poles of the magnets together.
Q634. According to Fleming's left hand rule which particles get deflected towards the left in Rutherford's experiment?
Positively charged.
Q635. Alpha particles are deflected by...............
Strong electric and magnetic field.
Q636. Radio isotopes are obtained by.............................
Artificial radioactivity.
Q637. Who is the first observer of natural radioactivity?
Henri Becquerel.
Q638. Crystal diffracts .........................................................
x rays.
Q639. What is required for the production of x rays?
High voltage and low pressure.
Q640. How many radioactive isotopes are produced?
More than 800.
Q641. Inside the Coolidge tube, the tungsten filament is coated with......................
Barium Oxide.
Q642. ..........................................acts as a cathode in the Coolidge tube.
Tungsten filament.
Q643. To get better observation of fluorescence, Roentgen covered the discharge tube with.....................
Thin black card board.
Q644. What is the unit of audible frequency of sound for human beings?
20 to 20000Hz.
Q645. Why does a man fall forward while jumps out of a running train?
He is in motion while in the train. When he jumps out, his feet come to rest while touching the ground but his upper portion which is still in motion, takes him forward.
Q646. Which apparatus regulates temperature automatically?
Thermostat.
Q647. Why does an ordinary glass tumbler crack when very hot tea is poured in it?
When the inner layer of the tumbler gets heated it expands before the outer Layer and an unequal or mild expansion of both layers cause the crack.
Q648. Who invented the bifocal lens?
Benjamin Franklin.
Q649. Why is a compass used as an indicator of direction?
The magnetic needles of a compass under the influence of the earth's magnetic field lie in a north-south direction. Thus we identify the direction.
Q650. .......................is produced in nuclear reactor.
Radio isotopes.
Q651. Hydrogen bomb works on the principle of ...................................
Uncontrolled chain reaction.
Q652. ....................................is formed when deuterium fuses with Tortrum.
Helium.
Q653. .....................................law states that whenever there is a change in magnetic flux Linked with a coil an emf is induced in it.
Faraday's law.
Q654. The induced emf is independent on.............................
Length of the magnet.
Q655. Lenz law is in accordance with the law of............................
Conservation of energy.
Q656. When is the mechanical force zero?
Conductor parallel to the field.
Q657. Domestic appliances are designed to operate at......................
220V.
Q658. Industrial electrical appliances are designed to operate at................
440V.
Q659. .............................is used in converting electrical energy into sound energy.
Loud Speaker.
Q660. The unit of mechanical force is.......................
N.
Q661. When the magnet is brought towards the coil, the number of magnetic lines of force linked with the coil............................
changes.
Q662. What is the unit of magnetic flux?
Weber.
Q663. What is venture tube?
A device to measure flow of liquids and their pressure.
Q664. Fleming's left hand rule is used to find the direction of.......
mechanical force on a current carrying conductor.
Q665. Why is water from a hand pump warm in winter and cold in summer?
In winter the outside temperature is lower than that of water flowing out of the pump and, therefore, it feels of warm. Whereas in summer the outside temperature is higher than that of water of the pump and therefore it feels cold.
Q666. The output and input currents in a transformer are 10A and 40A respectively. The transformer ratio is......................
4
Q667. The turn ratio in a step up transformer is...............
K=0.
Q668. Alternating current changes its direction .......................
periodically.
Q669. The transformer consists of insulated copper coils wound on either side of a........
Laminated soft-iron core.
Q670. To minimize the power loss, the electric power should be transmitted at.........
high voltage and high current.
Q671. In a step up transformer the input voltage is 440 V and the output voltage Is 2200 V. The ratio of number of turns of secondary to primary is...............
5:1.
Q672. Transformer ratio is the ratio of.....................
primary voltage to the secondary voltage.
Q673. In a transformer, the transformer ratio K is also known as.........
Turn ratio.
Q674. Who invented photo electric effect?
Hertz.
Q675. Which instrument is used for changing AC to DC?
Rectifier.
Q676. Why is a rainbow seen after a shower?
After a shower, the clouds containing water droplets act like a prism through which the white light is dispersed and produces a spectrum.
Q677. What is the speed of sound in air?
340 m/s.
Q678. In a step up transformer, voltage............................. and current .................................... .
increases, decreases.
Q679. A direct current consists of ....................................
positive half cycle.
Q680. During electric power transmission electric energy is dissipated in the form of........
heat energy.
Q681. The principle used in microphone is.........
electromagnetic induction.
Q682. According to Flemming's left hand rule, the middle finger represents the direction of...................................
Current in the conductor.
Q683. The electromagnetic force obtained from an AC generator can be increased by.......
strong magnetic field.
Q684. In AC generator the armature is rotated about its axis............................
perpendicular to the magnetic field.
Q685. The function of the carbon brushes in a DC motor is to.............................
Make a connection with a moving surface.
Q686. In electrical power lines, as a practice, the live wire is represented by.........
Green.
Q687. Flemming's right hand rule determines the ............................
direction of the current induced in a coil due to its rotation in a magnetic field.
Q688. When current in a conductor is switched off, the magnetic needle placed near its conductor....................................
gets back to its initial position.
Q689. In which direction the induced current acts?
opposite to the motion of the magnet.
Q690. The direction of the magnetic field at the centre of acircular coil carrying current can be found by.....................
Lenz Law.
Q691. The resistance of resistor.............................when the temperature is increased.
increases.
Q692. ..............................is used as a stand by during power failures.
AC generator.
Q693. ..........................................uses a split ring commutator.
DC generator.
Q694. Transmission of ...................................current is more expensive.
unidirectional.
Q695. .....................................converts the AC into DC.
Split rings.
Q696. ............................................transformer has less number of turns in the secondary than in the primary coil.
Step down.
Q697. ......................generator produces the unidirectional current.
DC.
Q698. By using .................................................the induced current in a coil can be increased.
a stronger magnet.
Q699. When the light level is increased, the resistance of a thermistor....................................
remains constant.
Q700. Why does a swimming pool appear less deep than it actually is?
The rays of light coming from the bottom of the pool pass from a denser medium (water) to a rarer medium (air) and are refracted (bend away from the normal).When the rays return to the surface they form an image of the bottom of the pool at a point which is little above the real position.
Q701. Which wave has the most wave length?
Radiowave.
Q702. Why does a kerosene oil float on water?
Because the density of kerosene oil is less than that of water. For the same reason, cream rises in milk and floats on the top.
Q703. One unit of electrical energy is.......................
1 Kwh.
Q704. .....................................material core is used in solenoid to make an electromagnet.
Soft iron.
Q705. The resistivity of a wire is independent of.......................
length, cross section and mass.
Q706. What is the specific gravity of water?
1
Q707. Why is one's breath is visible in winter but not in summer?
In winter water vapour contained in the breath condenses into small droplets which become visible but in summer they are quickly evaporated and thus not seen.
Q708. In which instrument microwaves were first produced?
Magnetron.
Q709. Electric current always flows.......................
from higher to lower potential.
Q710. Why does not the electric filament in an electric bulb burn up?
First because it is made of tungsten which has a very high melting point (3410 degreeC). Whereas the temperature of the filament required to glow is only 2700 degreeC. Secondly oxygen is absent since the bulb is filled with an inert gas which does not help in burning.
Q711. When does the movement of electrons occur?
potential difference between two points.
Q712. A body will float in a liquid if the buoyant force is.............................
equal to its weight.
Q713. Which of the three bulbs, 25W, 40W and 40W operating on 220V will have the lowest resistance?
60W.
Q714. How many 100W bulbs may be safely used on 220V with 5A fuse?
11
Q715. When the scattered light has a wavelength different from that of the incident light it is known as.....................
Incoherent scattering.
Q716. When an object undergoes acceleration............................
force always acts on it.
Q717. A substance cannot catch fire or burn as long as its temperature is lower than...................................
Ignition temperature.
Q718. The level of water in sea rises and falls due to the .............................
gravitational pull of moon on earth.
Q719. .....................................is based on electromagnetic induction.
Transformer.
Q720. The principle used in the galvanometer is.............................
Mechanical effect of electric current.
Q721. A transformer converts 220 V into 11 V, with 2000 turns in primary. What will be the number of turns in the secondary?
100
Q722. ...................................is created by the relative motion between coil and magnetic field.
Induced current.
Q723. ...................................is induced when magnetic lines are cut by a conductor.
Electromotive force.
Q724. .............................gave the first theory about the constituents of matter.
Dalton.
Q725. A ball dropped from a particular height reaches the ground with a velocity of 20 m/s. What is the height from which the ball was dropped?
20m.
Q726. ..................................................conducted an experiment by passing electricity through gases at reduced pressure.
J J Thomson.
Q727. Two wires of same material, length and diameters are first connected in series and then parallel in a circuit across the same potential difference. What is the ratio of heat produced in series and parallel combinations?
1:4.
Q728. The purpose of a Galvanometer is for ................
detecting the current flowing through the coil.
Q729. The direction of induced current was propounded by.........
Lenz.
Q730. In a moving coil galvanometer, the deflection produced is proportion to the...............
current in the coil.
Q731. Which type of photographic instrument is used to take photograph in mist and darkness?
Infra Red Camera.
Q732. Why does a small ball of iron sink in water but a ship float?
The weight of water displaced by an iron ball is less than its own weight, whereas water displaced by the immersed portion of a ship is equal to its own weight. (Archimedes principle). Same with ice floating on water.
Q733. In a moving coil galvanometer, the phosphor-bronze hair springs provides........
Restoring couple.
Q734. The mathematical expression for ohm's law is...............
V = IR.
Q735. A positive charge projected towards east is deflected towards north by a magnetic field. The magnetic field is directed.............................
Vertically downwards.
Q736. In DC motor, the effect of couple is to.......................
Rotate the coil.
Q737. What is the SI Unit of magnetic flux?
Wb.
Q738. The speed of the bob of a simple pendulum.............................
is maximum at the mean position.
Q739. The power of a DC motor can be increased by.....................................
increasing the current.
Q740. When the potential difference cross the ends of the conductor is halved, the amount of heat produced is..............
One fourth.
Q741. In biomass ............................energy is converted into electrical energy.
Chemical.
Q742. The speed of rotation of an electric motor can be increased by..............
increasing the strength of the magnetic field.
Q743. Polarity of an electromagnet gets reversed by..............................
Reversing the direction of current.
Q744. If two stream of protons move parallel to each other in the same direction, then they......................
attract each other.
Q745. Galvanometer can be converted into voltmeter by.............................
high resistance in series.
Q746. Who showed that a current carrying conductor placed in magnetic field Experiences a mechanical force?
Ampere.
Q747. Electric power is defined as.......................
Rate of doing work.
Q748. Which field is produced by a changed body at rest........
only electrical field.
Q749. What will happen when the direction of current in conductor is reversed, then The deflection of the needle of a compass placed near a carrying conductor?
Reverses its direction.
Q750. Property of a proton that can change while moving in a magnetic field is........
Velocity.
Q751. The coil used in DC motor is..............................
Armature.
Q752. When a wire carries an electric current in it, its temperature rises due to conversion of.........
Electrical into heat.
Q753. Two bulbs A and B are connected in series with a cell having resistance of Ra and Rb. What is the ratio of electric potential difference across A and B?
Ra:Rb.
Q754. An electric heater is connected to an ideal cell. The work done by the cell is ...................................heat generated by the heater.
Equal to.
Q755. An electric charge in uniform motion produces...................................
both electric and magnetic fields.
Q756. In a circuit containing two unequal resistors connected in parallel............................
the voltage drop across both the resistance is same.
Q757. A charged particle moving in a magnetic field experiences a resultant force.........
in the direction perpendicular to both the field and its velocity.
Q758. The change in magnetic flux linked with the coils A and B is same if the time taken to bring this change is more for the coil A, the emf induced in A is ......................................................... the emf induced in B.
less than.
Q759. The direction of magnetic lines produced by passing a direct current in a conductor is.....................
surrounding the conductor and are circular.
Q760. The resistivity of a wire depends on its......................
material.
Q761. The magnetic flux through the coil changes from 120 Wb to 240 Wb, when Magnet is moved towards it. If the change occurs in 0.5s, the emf induced in the coil is.........
240V.
Q762. A tumbler is filled to the brim and a piece of ice is placed in it. When the ice melts will the tumbler overflow?
Level of water remains unchanged because the volume of water produced by the melting ice is exactly the same as that of the piece of ice.
Q763. Why does a moisture gather outside a tumbler containing cold water?
The water vapour of air condences on cooling and appears as droplets of water.
Q764. The amount of heat generated by current of 0.5A flowing through a coil of resistance 6 ohm in one minute is............................
90
Q765. The radius of curvature of a convex mirror is 32 cm. Its focal length is.....................cm.
16
Q766. The commonly used fuse wire is made of............................
an alloy of Tin and lead.
Q767. Who made and activated the first nuclear reactor?
Enrico Fermi.
Q768. In an electric bell, we use a ...................................as the magnetism produced in the Rod is ......................................................... .
Soft iron rod, temporary.
Q769. What will be the charge on the other body that is attracted by a charged body?
Positive or Negative.
Q770. If the current flowing through an electric circuit is doubled, then the heat produced by the current in the circuit will be....................... ............... the initial value.
four times.
Q771. The two types of inter atomic forces that exist in the liquids are.......................
Cohesive and Adhesive.
Q772. The force of attraction between the molecules of the same substance is known as
Cohesive.
Q773. In solids, the cohesive force is very strong. True or False?
True.
Q774. A greased needle is gently placed on the surface of water. What happens?
It floats.
Q775. The change is relative position of the molecules, the body undergoes....................................
deformation.
Q776. The position of the image, when an object is placed at c, will be.....................
at c.
Q777. Where is the biggest solar plant in the world?
California.
Q778. Why is the water in an open pond cool even on a hot summer day?
Evaporation takes away the heat in the process, leaving the water surface cool.
Q779. The refraction of light is more in......................
Diamond.
Q780. Why is it difficult to cook rice or potatoes at higher altitudes?
Atmospheric pressure at higher altitudes is low and boils water at below 100 degreeC, because the boiling point of water is directly proportional to the Pressure on its surface.
Q781. Name the electrode that is connected to the negative pole of the battery?
Cathode.
Q782. According to Hooke's law, within the elastic limit, the stress is proportional to.......
strain.
Q783. The free surface of a liquid possesses.......................
Minimum surface area.
Q784. How are the atoms arranged in amorphous solids?
Disorderly manner.
Q785. When oil is added on the surface of water, the surface tension is....................................
increased.
Q786. In a streamline flow, the pressure within the fluid varies with..............................
velocity of the fluid.
Q787. .....................................alone exhibits the property of viscosity.
Liquids.
Q788. Dirty clothes having grease and oil stains cannot be washed with water. Why?
Because the surface tension is more.
Q789. The force of surface tension is always .......................to the liquid surface.
normal.
Q790. Due to very weak interatomic force, gas molecules ..............................
cannot move freely.
Q791. The aircraft experiences an upward force because of.....................................
low pressure above the wing.
Q792. The body which does not gain its original shape after the removal of deforming force is called..............................
Accelerated bodies.
Q793. The force developed within the body due to molecular displacement is called.................
Deforming force.
Q794. Convection can happen in.................................... .............................. ................................... .
liquids and gases.
Q795. The restoring force per unit area of a deformed body is known as.......................
Stress.
Q796. The force of surface tension is always ............................to the liquid surface.
Tangential.
Q797. Why is difficult to breathe at higher altitudes?
Due to low air pressure at higher altitudes, the quantity of air is less, so also that of oxygen.
Q798. Which is the colour of light emitted by hydrogen discharge lamps?
Blue.
Q799. Why are winter nights warmer and summer nights hotter in a cloudy weather?
Clouds being bad conductors of heat, do not permit radiation of heat from land. As the heat remains in the atmosphere making winter nights warmer and summer nights hotter.
Q800. The nucleus of which atom is equivalent to an alpha particles?
Helium.
Q801. Why are cloudy days cooler?
Because the clouds do not permit sun's rays to reach the earth.
Q802. Which fuel is used in Purnima-1 reactor?
Plutonium.
Q803. Why is a metal tyre heated before it is fixed on a wooden wheel?
On heating, the metal tyre expands by which its circumference also increases. this makes the fixing easier and thereafter cooling it down shrinks it thus securing the wheel tightly.
Q804. Honey, Castor Oil and Glycerine has higher ...................................force.
viscous.
Q805. Best absorbers of thermal radiation are..............................
Black and dull surfaces.
Q806. ....................................law gives the viscous force opposing the motion of a metal sphere through a highly viscous liquid.
Stoke's law.
Q807. Heat pass through a single pane of window glass by.....................
conduction and radiation.
Q808. What are the factors that give distinct properties to the liquids?
Interatomic force, Intermolecular force and Random motion of Molecules.
Q809. A distance time graph is parallel to X axis. What does it indicate?
Stationary position of the object.
Q810. The slope of velocity-time graph indicate.....................
acceleration.
Q811. Photo electric emission is an ....................................
Instantaneous process.
Q812. When an object moves with uniform motion, its acceleration will be............................
zero.
Q813. ....................................is used to analyse the chemical composition of different substances.
Raman's shift.
Q814. Which colour gets scattered more?
Blue.
Q815. The heat energy for geothermal energy comes from............................
Sun warming the ground.
Q816. For a given amount of energy released, which fuel releases the most Carbon-di-oxide?
Coal.
Q817. The change in magnetic flux of both coils A and B is same. If the time taken Is more in coil A, the emf induced in A is ..............the emf induced in B.
less than.
Q818. When a particle is moving in a circular path, its acceleration is,
directed towards the centre.
Q819. In which orbits an electron can revolve in..............
a few discrete and permitted orbits.
Q820. ..............................force provides electrostatic force between electron and nucleus.
Centripetal.
Q821. The moment of inertion of a rotating body depends upon ................
Angular velocity.
Q822. ...................................will not change when a wave goes from one medium to another.
Frequency.
Q823. 15Hz sound can be heard by human being. True or False?
False.
Q824. The inertia between a football and a stone of same size is.......
Stone is greater.
Q825. An object of 50Kg is moving with a speed of 20 m/s, the momentum of the object is............................
1000 kgm/s
Q826. .....................................law states the concept of inertia.
Newton's First Law.
Q827. When the mass of an object increased by four times and velocity is halved, the kinetic energy will be...................................
same as the previous kinetic energy.
Q828. Potential energy is decreased and Kinetic energy is increased ? this statement is applicable for an object falling freely. True or false?
True.
Q829. ............................................is used to detect the presence of an unseen water object.
SONAR.
Q830. What is the angle between displacement and force, to get maximum work?
0 degree.
Q831. The force acting on an object perpendicular to the surface is called..............................
Thrust.
Q832. Longitudinal waves are produced in.............................
solids, gases, and liquids.
Q833. If the time taken by a free falling body to reach the ground is 8 seconds, then what will be the height from where it started falling?
313.6 m.
Q834. In projectile motion, the object is thrown at an angle of............................
less than 90 degree.
Q835. In transverse waves the particles of medium oscillates............................
to perpendicular the direction of propagation.
Q836. The distance traveled by a wave in one second is its .....................................
velocity.
Q837. Small insects can move above on surface of water. How?
Because the surface tension of water is large.
Q838. "In the absence of air resistance, all bodies fall at the same acceleration: Who said this?
Galileo.
Q839. An object released from a certain height with a velocity of 40.2 m/s reaches the ground in.....................
4 s.
Q840. When the free falling body descends down, the velocity of the body...................................
increases.
Q841. When a stone tied to a string and rotated in a circular path, then the tension in the string provides...................................
centripetal force.
Q842. The centre of gravity die in a triangular body at ...................................
centroid.
Q843. Why is it easier to swim in sea water than in a river?
The density of sea water is higher and hence the upward thrust is more than that of river water.
Q844. Who formulated the theory that there are only three basic colours and what are they?
Thomas Young -- England -- Red, Blue Green.
Q845. Who will possibly learn swimming faster, a fat or a thin person?
A fat person displaces more water which will help him float more freely compared to that of the thin person.
Q846. Which device uses Pascal's Law?
Hydraulic Press.
Q847. Why does water remain cold in an earthen pot?
There are pores in the earthen pot which allow water to percolate to the outer surface. Here, evaporation of water takes place thereby producing a cooling effect.
Q848. A 5 cm long conductor carrying 8 A current is placed in a magnetic field of induction 2T, making an angle 30 degree with the field. What is the force acting on the conductor?
0.40N.
Q849. How to demagnetize a permanent magnet?
By placing it inside a solenoid carrying AC.
Q850. What is the temperature equal to 273 degree K?
0 degreeC.
Q851. Who was the first to use a sundial?
Anaxy Mander .... a philosopher.
Q852. A current carrying conductor is placed normal to the magnetic field directed towards east. The electrons in the conductor are moving from north to south. What is the direction of the force acting on the conductor?
Vertically upwards.
Q853. In a thermal power plant......................energy is transformed into electrical energy.
Chemical.
Q854. When current in a conductor is switched off, the magnetic needle placed near the conductor...................................
gets back to its initial position.
Q855. ............................................is used to measure the pressure in terms of the difference in fluid levels between the vertical arms of a U-tube?
Manometer.
Q856. A satellite is moving around the earth in a circular orbit with a velocity V. If the gravitational force of the earth were to suddenly disappear, then the Satellite would....................................
spirally move away from the earth.
Q857. To avoid heat by radiation the calorimeter is electroplated with......................
Nickel.
Q858. The electrochemical cells which make use of irreversible chemical reactions are..
Primary cells.
Q859. The electromagnets are widely used in the fields of...................................
Telephone, telegraph and motors.
Q860. When earth rotates about its own axis, the velocity of bodies near the equator is.............................that of at the poles.
more than.
Q861. Liquid exert pressure only............................
downwards.
Q862. The ink filler works on the principle of...............
air pressure.
Q863. If the sum of all the forces acting on a moving object is zero, the object will........
continue moving with constant velocity.
Q864. When a neutral metal sphere is charged by contact with a positively charged glass rod, the sphere................
Losses electrons.
Q865. A spring scale reads 10N as it pulls 5 kg mass across a table. What is the Magnitude of the force exerted by mass on the spring scale?
10N.
Q866. The current supply from is a conversion of ...................................energy into .............................energy.
chemical, electrical.
Q867. The heat gained or lost by a body during a change of state is.....................heat.
latent.
Q868. The heat gained or lost by a body resulting in a change in temperature is called....................................
Sensible heat.
Q869. Fusion point and ...................................occur at the same temperature.
Solidification point (freezing point).
Q870. One Newton approximately equals the force of gravity acting on an Object of .......................grams.
100
Q871. The amount of heat required to raise the temperature of a unit ............................of a material by 1 deg C is called specific heat capacity.
Mass.
Q872. Diamond's purity can be detected by.....................
X rays.
Q873. An object is placed at a distance of 10 cm from convex lens of focal length 15cm. Find the position and nature of the image?
Virtual, enlarged and erect.
Q874. A plane glass slab is kept over various colored letters. Which letter would appear least raised?
Red.
Q875. The gravitational force acting on an object is called its.....................
weight.
Q876. For which colour, the critical angle is minimum when light passes from glass to water?
Violet.
Q877. "Scattering of light by the colloidal particles" is a phenomenon known as........
Tyndall effect.
Q878. .............................produced electromagnetic waves experimentally.
Hertz.
Q879. When light incidents on a highly polished surface most of the light is.........
reflected.
Q880. The ratio of radius of curvature to focal length of a spherical mirror is......................
2:1
Q881. ....................................are emitted during photoelectric emissions.
Electrons.
Q882. In dispersion, the angle of deviation is maximum for ............................colour.
Red.
Q883. Angle between the incident and emergent rays are known as............................
Angle of deviation.
Q884. A person of 180 cm height wishes to see his full image in a mirror. The required length of mirror is.............................
90 cm.
Q885. The splitting of white light into colours is known as ......................
Dispersion.
Q886. Compound microscope forms a ............................image.
Virtual.
Q887. Radio waves are produced by...................................................
accelerated electric charges conducting through wire.
Q888. The frequency range of FM band is..............................
88MHZ to 108MHZ.
Q889. ...................................was the first to study the scattering of light experimentally.
Tyndall.
Q890. ....................................does not absorb IR rays.
Rock Salt.
Q891. ...........................................telescope is used for seeing in darkness.
Infrared.
Q892. Plants and humans when exposed to UV rays in small dose produce.........
Vitamin D.
Q893. Beta rays are not .......................................................................waves.
electromagnetic.
Q894. Ultraviolet rays are detected by..............................
J.Ritter.
Q895. Which instrument is used to measure the force of electric current?
Ammeter.
Q896. Why does an ordinary pendulum clock lose time in summer?
In summer, due to heat the length of the pendulum increases, which increases the duration of each oscillation of the pendulum thus losing time.
Q897. Why the petrol fire cannot be extinguished by water?
1. Water, which is heavier than petrol, slips down permitting the petrol to rise to the surface and continue to burn. 2. The temperature arising out of the burning is so high that the water poured on the fire evaporates even before extinguishing the fire, when the water poured is small in quantity.
Q898. Who is called the father of "Electricity"?
Michael Faraday.
Q899. What is the domestic electricity supply voltage?
230 Volts.
Q900. Above the threshold frequency, the photo electric current is..............................
directly proportional to the distance between the plates.
Q901. Radioactive nuclei emits...........................................rays.
gamma.
Q902. During the phenomenon of absorption, light behaves as............................
stream particles.
Q903. X-ray, y-ray, Infrared, Ultraviolet ... all of them............................
travel with same velocity in vacuums.
Q904. When a light of suitable frequency falls on a metal surface............................are ejected from the metal.
Electrons.
Q905. The minimum frequency below which there is no emission of photo electrons are called as.............................
Threshold frequently.
Q906. To read scripts which are not clearly visible for naked eye, the preferred lens would be......................
A convex lens of 3 cm.
Q907. Artificial radio activity emits only......................
Positron.
Q908. Why are mercury thermometers not used to measure very low temperature?
The freezing point of mercury is only.....................39 degreeC and it also has uniform Expansion at low temperature.
Q909. What is the commercial unit of electric charge?
Kwh.
Q910. Who is the inventor of atomic theory?
Democratis.
Q911. What is the speed of light?
300000 Km/s
Q912. Who proved that light travels faster than sound?
Olace Romer.
Q913. If an object is placed in front of a convex lens at a distance less than the focal Length, then the image formed is................and.......................
Magnified, erect.
Q914. The temperature of a body is a measure of the .................................................
Average PE of the molecules.
Q915. The size of the image formed by an object placed at the focus of a convex lens.......
highly enlarged.
Q916. The measure of the tendency of a material to slow down light at it travels through it is known as .......................
Optical density.
Q917. Tidal energy can best be obtained from.......................
oceans.
Q918. The basic problem with geothermal energy is.............................
not readily available.
Q919. Why do we place a wet cloth on the forehead of a patient from high temperature?
Due to body's temperature water evaporating from the wet cloth produces cooling and bring the temperature down.
Q920. In what form does the sound waves travel in air?
Longitudinal waves.
Q921. How does oil rise on a cloth tape of an oil lamp?
The pores in the cloth tape suck oil due to the capillary action of oil.
Q922. How many degree farenheit makes 0 deg C?
32 degreeF.
Q923. Why do we apply Eau-de-cologne to a person having high temperature?
Eau-de-cologne contains alcohol which is quickly evaporated and takes away much of the local heat from the body of the person.
Q924. What is the device that changes light energy into electric energy?
Photo electric cell.
Q925. When a needle is placed on a small piece of blotting paper which is placed on the surface of a glass of water, the blotting paper sinks after a few minutes but the needle floats. However, in a soap solution the needle sinks. Why?
The surface tension of clean water being higher than that of soap solution, it can support the weight of needle due to surface tension. However, when soap is added the surface tension of water reduces, which makes the needle to sink.
Q926. Who was the first to make electric magnet?
William Sturjor.
Q927. What is the scientific name for "Photostat"?
Xerography ... invented by C.F. Carrison.
Q928. What is absolute zero, the temperature at which the atom of a matter becomes still?
--273 degreeC or 0 degreeK.
Q929. To arrest or prevent the growth of mosquitoes, it is recommended to sprinkle Oil in the ponds with stagnant water. Why?
Mosquitoes breed in stagnant water and the larvae of mosquitoes keep floating on the surface of water due to surface tension. However, when oil is sprinkled, the surface tension of stagnant water is lowered resulting in the drowning and death of the larvae.
Q930. Why are chimneys of factories using boilers are kept high?
The gases produced in boilers are hot and lighter in weight tend to go up. The chimneys exhaust these gases above in the atomosphere without polluting the lower layer of atomosphere.
Q931. How does ink get filled in a fountain pen?
When the rubber tube of a fountain pen is immersed and pressed, the air inside the tube comes out and when the pressure is released, the ink rushes in to fill the space.
Q932. Which thermometer is used to find continuous changes in temperature?
Thermo electric thermometer.
Q933. What is the important advantage of sodimum vapor lamp?
Requires less electricity.
Q934. Which instrument determines the freezing point of a liquid?
Cryoscope.
Q935. Why are air coolers less effective during the rainy season?
During the rainy season the atmospheric air is saturated with humidity. Therefore, the process of evaporation of water from the moist pads of the Cooler slows down, thereby not cooling the air blown out from the cooler.
Q936. Instrument that measures the variations in gravitational field is?
Gravimeter.
Q937. Who started the "Indian Journal of Physics"?
Sir C.V.Raman.
Q938. Which scientist launched rocket for the first time on an experimental basis?
Robert H. Godard.
Q939. Why does grass gather more dew in nights than metallic objects like the stones?
Grass being a good radiator enables water vapour in the air to condense on it. Moreover, grass gives out water vapour in the form of dew because the air near grass is saturated with water vapour and slows evaporation. Dew is formed on objects which are good radiators and bad conductors.
Q940. Which law is applied in the working of rockets?
Newton's Third Law of Motion.
Q941. Which instrument is used to detect the presence of electric charge?
Electroscope.
Q942. Who was the first to produce battery which produce electric charge?
Alexandro Volta.
Q943. For which subject Albert Einstein received noble prize in 1921?
Photo Electric Effect .. Physics.
Q944. What principle is used in brakes?
Friction.
Q945. What is the basic principle followed in the construction of submarines?
Buoyancy ... Archimedes.
Q946. Why sound is not heard in the moon?
Because there is no atmosphere.
Q947. Who first constructed the telescope?
Galileo.
Q948. The total amount of living material in a unit of area is known as?
Biomass.
Q949. What percentage of solar energy reaching the earth's surface is converted Into Biomass?
0.2%.
Q950. Coal, Petroleum and Natural gas are examples of?
Fossil Fuels.
Q951. What is FM in Radio?
Frequency Modulation.
Q952. What is VHS with reference to Video?
Video Home System.
Q953. What is the speed of telecom signals?
About the speed of light.
Q954. What is the telecommunicational integration?
Doing different works in the same line.
Q955. Who discovered Fluorescence?
Sir George Stokes.
Q956. Who prepared Soda Water for the first time?
Joseph Priestley.
Q957. How many atoms are there in Ozone molecule?
Three.
Q958. Nuclear Reactors work on the principal of?
Nuclear Fission.
Q959. A device that converts one form of energy into another is..............
Transducer.
Q960. Heating element of electric heater is made of?
Nichrome.
Q961. The instrument for measuring the strength of the direct current is.........
Tangent Galvanometer.
Q962. The Physicist who originated "Quantum Theory"?
Masc Plank.
Q963. What is Mass energy equation?
E = mc2
Q964. The name of the energy quantum that has the highest velocity?
Photon.
Q965. A fuse wire is characterized by?
High resistance and low melting point.
Q966. "A body will remain at rest unless an external force acts on the body". Who said this?
Newton.
Q967. Which metal is commonly used as electromagnet?
Iron.
Q968. What do not admit any division?
Atom.
Q969. Choke is used to?
Give relatively large impedance of alternating current.
Q970. If the length of heater coil is reduced by a certain percentage, the current consumption will.........
increase by the same percentage.
Q971. Why a red light is used in traffic signals?
Because it has the longest wavelength, and can be seen from long distance.
Q972. Why metals are good conductors of electricity?
Because they have free electrons.
Q973. Why an iron rod gets heated quickly than a wooden piece when exposed to sunlight or heat?
Because of the greater thermal conductivity of Iron.
Q974. Why water should not be used to extinguish a fire caused by electric Current?
Being a good conductor, it may cause another short circuit.
Q975. How does ignition take place in a diesel engine?
Compression.
Q976. A sprayer works on the principle of........
Pascal.
Q977. Why do we feel breathless climbing over hills?
Approximate velocity of sound in air.
Q978. Why clouds do not precipitate in deserts?
Low Humidity.
Q979. An echo is produced by.........
Reflection of Sound.
Q980. What is the speed of light in water and consequent refractive index of water?
Speed of light in water is 3/4th of that in air and thus the refractive index of water is 4/3.
Q981. Among vacuum, steel, water and air, sound travels faster through which?
Steel.
Q982. What is conduction?
The process of transfer of heat by matter without actual movement of the Particles themselves.
Q983. Banking of curves is done to provide?
centripetal force.
Q984. In the case of a concave mirror, the image is......................?
Real, inverted and diminished when the object lies beyond the centre of curvature and focus.
Q985. What is essential to look in to decide a metal for making the cookware?
More thermal conductivity.
Q986. Sound waves having higher frequency than audio frequency is............................
Ultrasonic waves.
Q987. What is the source of solar energy?
Nuclear Fusion.
Q988. How the radar detects the presence of an enemy aircraft?
By Radiowaves.
Q989. Raman effect is used in the study of.......................?
Molecular energy.
Q990. What is a molecule?
The smallest unit of a substance that retains the properties of the substance.
Q991. The nucleus of an atom consists of......................
Protons and Neutrons.
Q992. Among the vessels made of Brass, copper, aluminium, and steel which one will get heated faster?
Copper vessel.
Q993. Among asbestos, celluloid, pertex and mica, which one is a good conductor of heat but a bad conductor of electricity?
Mica.
Q994. A sudden fall in barometer indicates?
Storm.
Q995. If the distance between two charges is halved, then the force between the two becomes?
Four times.
Q996. To increase the magnifying power of a telescope, the focal length of..............
Eye piece lens should be decreased.
Q997. What is the name for the bowl like silvered part of a reflector is called?
Parabola.
Q998. Concave lens bends light............................
outwards.
Q999. Convex lens bends light.....................
inwards.
Q1000. Television waves are ..............................
shorter than radio waves.
Q1001. An object moving around in a circle is moving .............................
with variable velocity.
Q1002. When water is heated from 0 to 10 deg C, the volume of water .......................
First decreases and then increases.
Q1003. The terms Hydraulic and Pneumatic relates to.......................
Hydraulic .. water. Pneumatic .. Air.
Q1004. What is "specific gravity"?
Ratio of density of a substance to the density of water at 4 degreeC.
Q1005. What is the freezing point of water on Kelvin Scale?
273.15K.
Q1006. What is "Positron"?
Antiparticle of an electron.
Q1007. What is the term for the total destruction of nuclear reactor?
Melt Down.
Q1008. In electric fittings, the wires are earthed because..............................
In case of a short circuit, current passes to the earth.
Q1009. PV=K is Boyle's law. What does the alphabets indicate?
P= Pressure of Gas; V=Volume of Gas; K=Constant.
Q1010. Among chromium, titanium, palladium, which one is used in aircrafts?
Palladium.
Q1011. What is the percentage of alcohol in Rectified Spirit?
95% (5% water).
Q1012. What are "Homologous" series?
A group of organic compounds having the same functional group.
Q1013. Force of Gravity on the moon is.....................
1/6th of what is on earth.
Q1014. When milk is churned, the cream from it is separated due to?
Centrifugal force.
Q1015. Ethanol is an important constituent of.......................
Beer, Wine, Whisky, Cough Syrups, and digestive syrups. (Commercial Ethanol is denatured to make it unfit for drinking).
Q1016. What is PTFE?
Poly Tetra Flurothene.
Q1017. What is IUPAC?
International Union of Pure and Applied Chemistry.
Q1018. What is PVC?
Poly Vinyl Chloride.
Q1019. How to measure the molecular weight of a substance?
Measuring vapour density.
Q1020. What is Anti-freeze?
A substance which lowers the freezing point of water. It is used in radiator of cars in cold countries.
Q1021. Which enzymes are required for fermentation of sugar cane to ethanol?
Zymase and Invertase.
Q1022. Why is mercury used as a thermometric fluid than water?
Because it has greater visibility.
Q1023. What is Mortar?
A thick paste of cement, sand and water.
Q1024. Magnetic field does not interact with........?
Stationary charge.
Q1025. What is added to cement to delay the setting time?
Gypsum.
Q1026. When water boils, its temperature remains............................
Constant.
Q1027. Water has maximum density at........?
4 degreeC.
Q1028. The critical angle of a glass slab increases with............................?
Decrease in the refractive index of glass.
Q1029. What happens when a recorded tape is played after being subjected to a magnetic field?
Recorded information is lost.
Q1030. Cosmic rays can be.....................
charged as well as uncharged.
Q1031. What is "Power Alcohol"?
A mixture of ethanol and petrol used as motor fuel.
Q1032. What is "EFFLORESCENCE"?
The property of some crystals to loose water of crystallization in dry is called so.
Q1033. The radius of curvature and focal length of a plane mirror is......................
infinite.
Q1034. Ray, wave and particles are...................................
Three nature of light propagation.
Q1035. What is the relation between angle of incidence and angle of reflection?
Equal.
Q1036. What is Refractive Index?
It is the speed of light in air (strictly in vacuum) to the speed in the medium.
Q1037. Which colour has the maximum refractive index?
Violet.
Q1038. Which colour has the minimum refractive index?
Red.
Q1039. What is the principle behind optical fibre?
Total internal reflection.
Q1040. What is the branch of physics which deals with different phenomena of light?
Optics.
Q1041. What happens to the light's frequency when it travels from air to glass?
Remains unchanged.
Q1042. To which colour eye is most sensitive?
The capacity or the ability of a lens to deviate (converge or diverge) the path of rays passing through it.
Q1043. What is "Looming" and the cause of it?
An optical illusion in which erect and virtual image of a distant object appears hanging in the mid air over the cold surface of snow. At a certain layer, total internal reflection takes place. It occurs in cold region due to Total Internal Reflection.
Q1044. What is critical angle?
The angle of incidence in denser medium for which angle of refraction is 90 degree in rarer medium.
Q1045. What should be the height of a plane mirror to get the full image of a person?
Half the height of the person.
Q1046. What type of mirror is used in solar water heater?
Concave.
Q1047. What is the cause of the brilliance of diamond?
Due to the edges of diamond are cut in such a way that total internal Reflection takes place due to its high refractive index.
Q1048. What is the focal length of a spherical mirror?
It is the distance between the pole and focus of the mirror.
Q1049. What is monochromatic light?
The light which consists only one wavelength.
Q1050. What is point of incidence?
The point on a reflecting surface at which a ray of light strikes the surface.
Q1051. What is Diffused Reflection?
If the parallel beams of light, falling on irregular objects like a paper, ground, wall etc., it is reflected in different directions, then this reflection is called diffused reflection. The diffused reflection helps in producing soft illumination for eyes.
Q1052. What is lens?
A transparent medium having two refracting surfaces out of which atleast one is curved. (general spherical)
Q1053. Who proposed the "Plum Pudding" model of the atom in 1897?
J.J.Thompson.
Q1054. What is "Mass Energy Equivalence"?
A concept that all objects with mass have an associated energy.
Q1055. What is "Photon"?
A packet of energy which moves with speed of light.
Q1056. In a wave, what is the distance, up or down, from rest called?
Amplitude.
Q1057. For a pendulum, how does the frequency vary with length?
Inversely.
Q1058. Refraction is due to.........?
Light changing speed.
Q1059. The distance between one of the magnetic polex and the centre of the bar magnet is................?
Length of the magnet.
Q1060. The radio frequency range of 30 to 300 MHzs is called.......................
VHF ... Very high frequency.
Q1061. What is the name of the process for the first step of getting output from a laser by exciting an active medium?
Pumping.
Q1062. Once the active medium is excited, the first photons of light are produced by?
Spontaneous emission.
Q1063. What was the active medium used in the first working laser ever constructed?
A Ruby road.
Q1064. How many protons are there in carbon atoms?
six.
Q1065. Magnet gets its name from ........
A place called Magnesia on the ancient Maeander River in Turkey.
Q1066. At what temperature is water said to boil on top of Mount Everest?
68 to 70 degreeC.
Q1067. Light consists of a bundle of energy called............................
Quanta.
Q1068. At what temperature water boils in Leh, Tibet?
78 degreeC.
Q1069. What frequency range is "high frequency"?
3 to 30 MHz.
Q1070. In Kelvin Scale what is the freezing point of water?
273.15K.
Q1071. At what degree paper automatically burns?
451 degreeF.
Q1072. Newton is the derived unit of.......................
Force.
Q1073. What is the derived unit of energy?
Joule.
Q1074. What type of rays are used in night vision apparatus?
Infrared rays.
