Assertion : A body is momentarily at rest at the instant it reverses the direction.
Reason : A body cannot have acceleration if its velocity is zero at a given instant of time.

Options

A. If both Assertion and Reason are correct and Reason is the correct explanation of assertion.
B. If both Assertion and Reason are correct but Reason in not the correct explanation of Assertion.
C. If Assertion is true but Reason is false.
D. If Assertion is false but Reason is true.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states: "A body is momentarily at rest at the instant it reverses the direction."
- When an object is moving in one direction and then starts to move in the opposite direction, it must first come to a stop (velocity = 0) before it can change direction. This implies that at the instant of direction reversal, the object is indeed momentarily at rest.

### Step 2: Understand the Reason
The reason states: "A body cannot have acceleration if its velocity is zero at a given instant of time."
- This statement is incorrect. An object can have zero velocity at a specific instant while still experiencing acceleration. For example, when an object is thrown upwards, it momentarily stops at its highest point (zero velocity) but is still under the influence of gravitational acceleration acting downwards.

### Step 3: Conclusion
- The assertion is true because a body does come to rest momentarily when it reverses direction.
- The reason is false because a body can have acceleration even when its velocity is zero.

### Final Answer
The correct option is that the assertion is true, but the reason is false.

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