Question

Assertion :A wheel moving down a perfectly frictionless inclined plane will undergo slipping (not rolling motion) Reason: For perfect rolling motion, work done against friction is zero.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is B Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

As the inclined plane surface is smooth, thus there is no friction force between the surface and the wheel.

Due to $mgsin\theta$, the wheel moves along the inclined surface.

Torque is responsible for the rotational motion of a body. But torque acting on the wheel about point O is zero. Hence the wheel does not exhibit the rotational motion.

Hence the wheel slips in downward direction on the inclined plane surface.

During a pure rolling motion, the contact point between the surface and the body remains at rest at every instant. Thus work done against the friction is zero.

Hence both Assertion and the reason statement are correct but reason is not the correct explanation of the Assertion.