set 5 MCQ Questions & Answers Detailed Explanation

Question : 1

Statement A :
When a gun is fired it recoils, i.e., it pushes back, with much less velocity than the velocity of the bullet.
Statement B :
Velocity of the recoiling gun is less because the gun is much heavier than the bullet.

a) Both statements are correct.

b) Statement B is correct.

c) Statement A is correct.

d) Both statements are incorrect.

Question : 2

Ball bearings are used in bicycles, cars, etc., because

a) the effective area of contact between the wheel and axle is reduced

b) the effective area of contact between the wheel and axle is increased

c) the actual area of contact between the wheel and axle is increased

d) None of the above statements is correct

Question : 3

The maximum kinetic energy of a planet moving around the sun is at a position

a) C

b) B

c) A

d) D

Question : 4

If suddenly the gravitational force of attraction between the earth and a satellite revolving around it becomes zero, then the satellite will

a) become stationary in its orbit

b) move tangentially to the original orbit with same speed

c) continue to move in its orbit with same speed

d) move towards the earth

Question : 5

If the earth stops rotating about its axis, the acceleration due to gravity will remain unchanged at

a) latitutde 60°

b) latitude 45°

c) equator

d) poles

Question : 6

A particle oscillates in one dimension about the equilibrium position subject to a force $F_x$(x) that has an associated potential energy U(x). If k is the force constant, which one of the following relations is true?

a) U(x) = $1/2$kx

b) $F_{x}(x) = –kx$

c) $F_{x}(x) = –kx^2$

d) U(x) =$1/2k^2x$