(A):A body may be accelerated even when it is moving at uniform speed.
(R ):When direction of motion of the body is changing then body may have acceleration.

Answer

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 may be accelerated even when it is moving at uniform speed."

- **Explanation**: Uniform speed means that the magnitude of the speed is constant, but it does not necessarily mean that the velocity is constant. Velocity is a vector quantity, which includes both magnitude and direction. If the direction of the body’s motion changes, the velocity changes even if the speed remains constant.

### Step 2: Understand the Reason
The reason states: "When the direction of motion of the body is changing, then the body may have acceleration."

- **Explanation**: This statement is true. Acceleration is defined as the rate of change of velocity. If the direction of the velocity changes (even if the speed is constant), there is a change in velocity, which means there is acceleration. A common example is uniform circular motion, where an object moves in a circle at a constant speed but continuously changes direction.

### Step 3: Evaluate the Assertion and Reason
Now, we need to evaluate the correctness of both statements:

- The assertion is incorrect because a body moving at uniform speed does not experience acceleration unless its direction changes.
- The reason is correct because a change in direction implies a change in velocity, which results in acceleration.

### Conclusion
- **Assertion (A)**: Incorrect
- **Reason (R)**: Correct

Thus, the final answer is that the assertion is incorrect, but the reason is correct.