(A) : Force is required to move a body uniformly along a circle.
(R) : When the body is in uniform circular motion, acceleration is zero.

Options

A. Both (A) and (R) are true and (R) is the correct explanation of (A)
B. Both (A) and (R) are true and (R) is not the correct explanation of (A)
C. (A) is true but ( R) is false
D. Both (A) and (R ) are false

Answer

To solve the question, we need to analyze the two statements provided:

1. **Assertion (A)**: Force is required to move a body uniformly along a circle.
2. **Reason (R)**: When the body is in uniform circular motion, acceleration is zero.

### Step-by-Step Solution:

**Step 1: Analyze the Assertion (A)**
- The assertion states that a force is required to move a body uniformly along a circle.
- According to Newton's first law of motion, an object will remain at rest or move in a straight line at constant speed unless acted upon by a net external force.
- In the case of circular motion, even if the speed is constant, the direction of the velocity is continuously changing. This change in direction requires a centripetal force directed towards the center of the circle.
- Therefore, the assertion is **true**.

**Step 2: Analyze the Reason (R)**
- The reason states that when a body is in uniform circular motion, acceleration is zero.
- In uniform circular motion, while the speed (magnitude of velocity) remains constant, the direction of the velocity vector changes continuously.
- Acceleration is defined as the rate of change of velocity. Since the direction of the velocity is changing, there is a non-zero acceleration (centripetal acceleration) directed towards the center of the circle.
- Therefore, the reason is **false**.

**Step 3: Conclusion**
- The assertion (A) is true, while the reason (R) is false.
- Thus, the correct answer is that A is true, but R is false.