155. Rate of change of momentum takes place in the direction

A.Of motion

B.Of applied force

C.Opposite to the direction of applied force

D.Perpendicular to the direction of motion

156. If the momentum of a given body is doubled, its kinetic energy will

A.Increase by 2 times

B.Increase by four times

C.Remain same

D.Get halved

157. If a ball which is dropped from a height of 2.25 m on a smooth floor attains the height of bounce equal to 1.00 m, the coefficient of the restitution between the ball and the floor is equal to

A.0.25

B.0.5

C.0.67

D.0.33

158. A ball moving with a velocity of 5 m per sec impinges on a fixed plane at an angle of 45°, its direction after impact is equally inclined to the line of impact. If coefficient of restitution is 0.5, the velocity of the ball after impact will be

A.0.5 m/sec

B.1.5 m/sec

C.2.5 m/sec

D.3.5 m/sec

159. Pick up the correct statement from the following : A rubber ball when strikes a wall rebounds but a lead ball of same mass and velocity when strikes the same wall falls down

A.Both undergo an equal change in momentum

B.The change in momentum suffered by lead ball is less than that of rubber ball

C.The momentum of rubber ball is less than that of lead ball

D.All of the above

160. Two pieces of steel and brass weighing 2 kg and 1 kg fall freely under action of gravity from a tower. After a distance, the following will be identical

A.Acceleration

B.Momentum

C.Kinetic energy

D.Potential energy

161. If a solid and a hollow sphere of the same mass are allowed to roll down an inclined plane simultaneously, then

A.Solid sphere will reach the ground first

B.Hollow sphere will reach the ground first

C.Both will reach the ground at the same time

D.Unpredictable

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