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1) How much time does sunlight takes to reach the Earth?

a) 2 minutes.
b) 4 minutes.
c) 8 minutes.
d) 16 minutes.

ANSWER : 8 minutes

2) The absorption of ink by blotting paper involves:

a) Viscosity of ink.
b) Capillary action phenomenon.
c) Diffusion of ink through the blotting.
d) Siphon action.

ANSWER : Capillary action phenomenon

3) Sound waves in air are:

a) Transverse.
b) Longitudinal.
c) Electromagnetic.
d) Polarised.

ANSWER : Longitudinal

4) Magnetism at the centre of a bar magnet is:

a) Minimum.
b) Maximum.
c) Zero.
d) Minimum or maximum.

ANSWER : Zero

5) Stars appears to move from east to west because:

a) All stars move from east to west.
b) The Earth rotates from west to east.
c) The Earth rotates from east to west.
d) None of these.

ANSWER : The Earth rotates from west to east

6) Why are metals good conductors of electricity?

a) The atoms are lightly packed.
b) They have high melting point.
c) They contain free electrons.
d) All of the above.

ANSWER : They contain free electrons

7) Why it is more difficult to walk on a sandy road than on a concrete road?

a) The friction between sand and feet is less than that between concrete and feet.
b) Sand is soft and concreter is hard.
c) The friction between sand and feet is more than that between concrete and feet.
d) The sand is grainy but concrete is smooth.

ANSWER : The friction between sand and feet is less than that between concrete and feet

8) On a rainy day, small oil films on water show brilliant colours. This is due to:

a) Diffraction.
b) Polarization.
c) Dispersion.
d) Interference.

ANSWER : Interference

9) In Sanskrit which among the following is known as ‘deer’s thirst’?

a) Halo.
b) Earthshine.
c) Mirage.
d) Rainbow.

ANSWER : Mirage

10) Why does star twinkle?

a) The light from the star is scattered by the dust particles and air molecules in the earth’s atmosphere.
b) The refractive index of the different layers of the earth’s atmosphere changes continuously, consequently the position of the image of a star changes with time.
c) The intensity of light emitted by them changes with time.
d) The distance of the stars from the earth changes with time.

ANSWER : The refractive index of the different layers of the earth’s atmosphere changes continuously, consequently the position of the image of a star changes with time

11) Sound travels at the fastest speed in:

a) Vacuum.
b) Air.
c) Water.
d) Steel.

ANSWER : Steel

12) On a cold day when a room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature, because:

a) Metals are good conductor of heat.
b) Plastics have a lower density than metals.
c) Plastics have a higher thermal conductivity than metals.
d) Metals have higher thermal capacity than plastics.

ANSWER : Metals are good conductor of heat

13) Intensity of sound at a point is …………its distance from the source.

a) Directly proportional to square of
b) Directly proportional to
c) Inversely proportional to.
d) Inversely proportional to square of

ANSWER : Inversely proportional to square of

14) Why are radio telescopes better than optical telescopes?

a) They can work during day and night.
b) They can work even in cloudy conditions.
c) They can detect faint galaxies which no optical telescope can.
d) All of the above.

ANSWER : All of the above

15) Among the following which does not have identical dimension?

a) Work and Torque.
b) Moment of inertia and moment of a force.
c) Impulse and Momentum.
d) None of these.

ANSWER : Moment of inertia and moment of a force

16) Why is mercury commonly used as a thermometric fluid than water?

a) Density of mercury is more than the water.
b) Specific heat of mercury is more than water.
c) Mercury has greater visibility than water.
d) Specific heat of mercury is less than water.

ANSWER : Mercury has greater visibility than water

17) Supersonic plane fly with the speed:

a) Of light.
b) Of sound.
c) Less than the speed of sound.
d) Greater than the speed of sound.

ANSWER : Greater than the speed of sound

18) Rainbow appears due to:

a) Refraction and reflection of sunlight by water droplets.
b) Diffusion of sunlight through water droplets.
c) Ionization of water deposits.
d) Absorption of sunlight in minute water droplets.

ANSWER : Refraction and reflection of sunlight by water droplets

19) When does solar eclipse take place?

a) The moon is between the sun and the earth.
b) The sun is between the moon and the earth.
c) The earth is between the moon and the sun.
d) None of these.

ANSWER : The moon is between the sun and the earth

20) Who among the following discovered natural radioactivity?

a) Henry Baquerel.
b) Ernest Rutherfor.
c) Marie Curie.
d) Enrico Fermi.

ANSWER : Henry Baquerel