Question

Assertion: A body can have acceleration even if its velocity is zero at a given instant of time.

Reason: A body is numerically at rest when it reverses its direction.

• 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 A

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.

Explanation for Assertion:

Acceleration: The change in velocity with respect to time is known as acceleration.

Formula: $a=\frac{dv}{dt}$

1. When the velocity of an object is zero, It still can have some change in velocity.
2. Consider the example of a body moving in a positive x-axis with some velocity say $v=2m/s$, now the body slows down and turns back and starts moving in the negative x-axis with some velocity $v=2m/s$
3. In this process the body has zero velocity at an instant, but it is constantly changing its velocity in the form of changing the direction at that particular instant.

The explanation for Reason:

From the above example, we can conclude that there can be acceleration for a body when its velocity is zero and it is due to the change in direction of the body.

Hence, the correct answer is option A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.