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Q1. When the freely falling body descends down the velocity of the body

Increases and then decreases

Decreases

Increases

Decreases and then increases

Q2. When the length of wire is halved what’ will be the resistance?

constant

Halved

Doubled

Tripled

Q3. When the coin is dropped, the force acting on it is

Gravitational

Electrostatic

Magnetic

Mechanical

Q4. When the electrons are moving in the discrete and permitted orbit they

Do not radiate energy

Do not possess angular momentum

Give out spectral lines

Give out radiate energy

Q5. When one neutron disintegrates, it produces

One proton and one electron

One proton

One proton and one neutron

One electron and one neutron

Q6. When objects at different distances are seen by the eye, which of the following remain constant?

The object-distance from the eye lens

The focal length of the eye lens

The image distance from the eye lens

The radii of curvature of the eye lens.

Q7. When meteors enter earth’s atmosphere, they get burnt due to

Collision

Fusion

Friction

Very high velocity

Q8. When more than one resistors are in series, which quantity remains the same?

Current

Potential difference

Resistance

None of the above

Q9. When light incidents on a highly polished surface most of the light is

Reflected

Refracted

Absorbed

Diffracted

Q10. When magenta, yellow and cyan are added which colour is obtained.

Green

Blue

Red

White.

Q11. When it is possible to observe total internal reflection?

A ray travels from air into water

A ray travels from air into glass

A ray travels from water into glass

A ray travels from glass into water.

Q12. When light goes from rarer to denser medium

Angle of incidence > angle of refraction

Angle of incidence < angle of refraction

Angle of incidence angle = angle of refraction

Angle of incidence > angle of reflection

Q13. When is the movement of electrons occurs?

There is a temperature difference between two points

Potential difference between two points

Both points must be of same potential

Electrons flow without any temperature and potental difference between two points.

Q14. When is the mechanical force zero?

Current carrying conductor placed towards west

Conductor placed towards east

Conductor parallel to the field

Conductor perpendicular to the field.

Q15. When is a prism said to be in minimum deviation?

i = angle of emergence

Angle of incidence > angle of emergence

i < angle of emergence

i = 0

Q16. When intensity of the incident radiation increases, what happens to the photoelectric current?

Increases

Does not change

Decreases

Remains the same.

Q17. When impurity is added then the melting point of ice

Increases

Decreases

Constant

No change.

Q18. When electrons revolve in the permissible non-radiating orbit, they

Give spectral lines

Possess a definite angular momentum

Do not give spectral lines

Do not posses a definite angular momentum

Q19. When earth rotates about its own axis, the velocity of bodies near the equator is ......... that of at the poles

Less than

More than

Equal to

None.

Q20. When current passes through a straight conductor, the magnetic field lines around it are in the form of with the conductor at the centre

Concentric circles

Ellipsoidal

A ring

A Parabola

Q21. When current in a conductor is switched off, the magnetic needle placed near the conductor

Gets deflected in the reverse direction

Does not change its position

Will be perpendicular to the length of the conductor

Gets back to its initial position.

Q22. When current in a conductor is switched off, the magnetic needle placed near its conductor .............

Gets deflected in the reverse direction

Does not change its position

Gets back to its initial position

Will be perpendicular to the length of the conductor.

Q23. When atom bomb explodes a large amount of ..........

Gamma radiations produced

Radio active radiations and neutrons are produced.

IR radiations release

Radio active radiations and photons are released.

Q24. When an object undergoes acceleration

Its speed always increases

Velocity always increases

Force always acts on it

It always falls towards the earth.

Q25. When an object starts to fall freely which statemtnet is correct about it?

Its P.E is increased and K.E is decreased

P.E remains unchanged

KE remains unchanged

P.E is decreased and KE is increased.

Q26. When an object reflects all the colours of white light, how does the object appear?

Black

Yellow

Blue

White.

Q27. When an object of 3 cm height is placed in front of a mirror, the magnification produced by the mirror is 8, what is the size of the image formed by the mirror?

5 cm

24 cm

2.3 cm

42 cm

Q28. When an object is thrown up, what is the value of g?

8.9 ms–2

9.8 ms–2

–9.8m/s2

–8.9m/s2

Q29. When an object is placed in front of a thick glass mirror how many images are formed?

Multiple

One

Q30. When an object is placed between pole and principal focus of a concave mirror, where the image is formed?

Beyond the centre of curvature

Behind the mirror

At the focus

At centre of curvature.

Q31. When an object is placed at the focus of a concave mirror, the image formed by the concave mirror is not

Inverted

Real

Virtual

Highly magnified.

Q32. When an object absorbs all the colours of white light the object appears.

Black

Yellow

Blue

White.

Q33. When an object 2 cm high is placed in front of a mirror, the magnification produced by the mirror is 4. What is the size of the image?

Q34. When an insect Walks on the surface of water, the force of surface tension acts

Along an inclined direction

Horizontally

Vertically

Downward direction.

Q35. When an a - particle is emitted the atomic number decreases by

Q36. When an external force of sufficient magnitude is applied on a body of some mass, the body acquires

Elasticity

Retardations

Inertia

Acceleration

Q37. When aluminium is bombarded by a-particle which isotope is produced?

Oxygen

Sulphur

Nitrogen

Phosphorus

Q38. When a wire carries an electric current in it its temperature rises due to conversion of

Thermal energy into electrical

Potential into heat

Electrical into heat

Chemical into heat

Q39. When a stone is tied to a string and rotated in a circular path then the tension in the string provides

Centrifugal force

Centripetal force

Gravitational force

Electrostatic force

Q40. When a steel rod is used in the place of soft iron rod in an electric bell .............

Frequency of the sound produced is more

Intensity of the sound produced is more

Bell does not ring continuously

Bell rings using less power.

Q41. When a solid is heated it changes into liquid is called

freezing

melting

vapourisation

sublimation

Q42. When a ray or light enters a glass slab from air

Its wavelength increases

Its wavelength decreases

Its frequency increases

Neither its wavelength nor its frequency changes.

Q43. When a particle is moving in a circular path, its acceleration is

Directed towards the centre

Along the circumference

Directed away from the centre

Along the tangents

Q44. When a painting brush is dipped in water, its hairs

Become thick

Thin out

Cling together

Spread out

Q45. When a nucleus emits g- rays, what is the change in atomic and mass numbers?

Increased by 2

Decreased by 1

Increased by 1

No change.

Q46. When a neutron converts itself into a proton which is obtained?

Electron

Positron

Neutron

Antineutron

Q47. When a neutral metal sphere is charged by contact with a positively charged glass rod. the sphere

Loses electrons

Gains electrons

Loses protons

Gains protons.

Q48. When a liquid evaporates, its temperature

Rises

Does not change

Falls

May rise or fall depending upon the situation.

Q49. When a light of suitable frequency falls on a metal surface ................. are ejected from the metal

Protons

Electrons

Neutrons

Photons

Q50. When a light goes from glass (mg = 3/2) to water (mw = 4/3), what is the refractive index of water with respect to glass?

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