Assertion: Center of mass and center of gravity of a body will coincide on moon.
Reason: There is no gravity on moon.

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 is 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 that the center of mass and center of gravity of a body will coincide on the moon.

- **Center of Mass**: This is the point where the mass of a body is concentrated. It depends on the distribution of mass within the body.
- **Center of Gravity**: This is the point where the weight of the body acts. It depends on the gravitational field acting on the body.

### Step 2: Analyze the Reason
The reason states that there is no gravity on the moon.

- This statement is incorrect. The moon does have gravity, although it is weaker than that of Earth. The gravitational acceleration on the moon is approximately 1/6th that of Earth.

### Step 3: Evaluate the Assertion and Reason
Since the moon does have gravity, we need to consider the nature of the gravitational field on the moon.

- The gravitational field on the moon is uniform across its surface. This means that the gravitational force acts equally on all parts of the body.

### Step 4: Conclusion
For a uniform gravitational field, the center of mass and center of gravity will coincide. Therefore, the assertion is true.

- **Assertion**: True (the center of mass and center of gravity coincide on the moon).
- **Reason**: False (the moon does have gravity).

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

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