Question

Assertion : The velocity of a body at the bottom of an inclined plane of given height is more when it slides down the plane compared to when it is rolling down the same plane.

Reason : In rolling down, a body acquires both kinetic energy of translation and rotation.

(a) Both A and R are true and R is the correct explanation of A

(b) Both A and R are true but R is not correct explanation of A

(c) A is true but R is false

(d) A and R are false

Answer 1

Correct option (b) Both A and R are true but R is not correct explanation of A

Explanation :

When a body slides, its entire PE is converted into KE of translation. But when it rolls down, some part of its PE is converted into its KE of rotation, thereby reducing its K.E of translation and hence its linear velocity.