UPSC MCQs Quiz 6: Science (Physics) with answers
1. A noise level of 100 decibel would correspond to [IAS 2000]
- just audible sound
- ordinary conversation
- sound from a noisy street
- noise from a machine shop
2. Which of the following statements is false?
- A body can have zero velocity and still be accelerated
- A body can have a constant velocity and still have a varying speed
- A body can have a constant speed and still have varying velocity
- The direction of the velocity of a body can change when its acceleration is constant
3. A ball is thrown upwards and it returns to ground describing a parabolic path. Which of the following remains constant?
- Kinetic energy of the ball
- Speed of the ball
- Horizontal component of velocity
- Vertical component of velocity
4. A piece of paper and a cricket ball are dropped from the same height. Under which of the following conditions do both reach the surface simultaneously?
- They must have the same volume
- They must have the same density
- They must have the same mass
- They must be dropped in vacuum
5. A bullet is fired from a rifle. If the rifle recoil freely, the kinetic energy of the rifle in comparison to that of the bullet is
- Nothing can be said
6. In which case does the potential energy decrease?
- On compressing a spring.
- On stretching a spring.
- On moving a body against gravitational force.
7. When a bicycle is in motion by pedalling, the force of friction exerted by the ground on the two wheels is such that it acts
- in the backward direction on the front wheel and in the forward direction on the rear wheel
- in the forward direction on the front wheel and in the backward direction on the rear wheel
- in the backward direction on both front and the rear wheels
- in the forward direction on both front and the rear wheels
8. The intensity of earth’s gravitational field is maximum at
- the equator
- the pole
- the centre of the earth
- None of the above
9. If the distance between two masses is doubled, the gravitational attraction between them
- is doubled
- is reduced to half
- becomes four times
- is reduced to quarter
10. If a pendulum clock is brought on the moon, then the period of oscillation of the pendulum clock becomes
- 1. (d)
- 2. (b)
- 3. (c)
- 4. (d)
- 5. (c)
- 6. (a)
- 7. (a)
- 8. (b)
- 9. (b)
- 10. (b)