Assertion: The average velocity of a particle is zero in a time interval. It is possible that the instantaneous acceleration is never zero in the interval.
Reason: The magnitude of average velocity in an interval is equal to its average speed in that interval.

Options

A. If both assertion `&` Reason are True `&` the Reason is a corrrect explanation of the Asserion.
B. If both Assertion `&` Reason are True but Reason is not correct explanation of the Assertion.
C. If Assertion is Trie but the Reason is False.
D. If both Assertion `&` Reason are false

Answer

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

### Step 1: Understand the Assertion
The assertion states that "The average velocity of a particle is zero in a time interval. It is possible that the instantaneous acceleration is never zero in the interval."

- Average velocity is defined as the total displacement divided by the total time taken. If a particle returns to its starting point after a time interval, its displacement is zero, leading to an average velocity of zero.
- Instantaneous acceleration can be defined as the rate of change of velocity at a specific instant. It can be non-zero even if the average velocity is zero.

### Step 2: Analyze the Reason
The reason states that "The magnitude of average velocity in an interval is equal to its average speed in that interval."

- Average speed is defined as the total distance traveled divided by the total time taken. The average speed and average velocity are not always equal; they are equal only when the motion is in a straight line without changing direction.
- In the case where the particle returns to the starting point (like in circular motion), the average velocity can be zero while the average speed is not.

### Step 3: Conclusion
- The assertion is true: it is possible for the average velocity to be zero while the instantaneous acceleration is not.
- The reason is false: the magnitude of average velocity is not necessarily equal to average speed, especially in cases of circular motion or any motion where the direction changes.

### Final Answer
Thus, the correct option is: **Assertion is true, but the reason is false.**

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