Assertion: A uniform circular motion is an acceleration motion.
Reason: Direction of acceleration is parallel to velocity vector.

Explanation

To analyze the given assertion and reason, we will break it down step by step.

### Step 1: Understanding Uniform Circular Motion
Uniform circular motion refers to the motion of an object traveling in a circular path at a constant speed. While the speed remains constant, the direction of the velocity vector changes continuously.

**Hint:** Remember that in uniform circular motion, the speed is constant, but the direction of motion changes.

### Step 2: Identifying Acceleration in Uniform Circular Motion
In uniform circular motion, even though the speed is constant, the object is accelerating because its direction is changing. This type of acceleration is called centripetal acceleration, which always points towards the center of the circular path.

**Hint:** Think about how acceleration is defined. It involves a change in velocity, which can occur due to a change in speed or direction.

### Step 3: Analyzing the Assertion
The assertion states that "a uniform circular motion is an acceleration motion." This is true because the object in uniform circular motion experiences centripetal acceleration due to the continuous change in direction of the velocity vector.

**Hint:** Consider the definition of acceleration and how it applies to changing velocity.

### Step 4: Analyzing the Reason
The reason states that "the direction of acceleration is parallel to the velocity vector." This statement is incorrect. In uniform circular motion, the velocity vector is tangential to the circular path, while the acceleration vector (centripetal acceleration) points radially inward, towards the center of the circle. Therefore, they are perpendicular to each other, not parallel.

**Hint:** Visualize the circular motion and the direction of both the velocity and acceleration vectors.

### Step 5: Conclusion
Based on the analysis:
- The assertion is **true**: Uniform circular motion is indeed an acceleration motion due to the change in direction of the velocity.
- The reason is **false**: The direction of acceleration is not parallel to the velocity vector; they are perpendicular.

### Final Answer
Assertion: True
Reason: False