According to right hand thumb rule, the direction of angular displacement when a particle is performing uniform circular motion is

Options

A. paraller to radius vector direction away
B. tangent to circular path
C. path prependicular to plane of circular path
D. directed along radius towards centre

Answer

To determine the direction of angular displacement when a particle is performing uniform circular motion according to the right-hand thumb rule, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Uniform Circular Motion**:
- Uniform circular motion refers to the motion of a particle moving in a circular path at a constant speed. Although the speed is constant, the direction of the velocity vector changes continuously.

2. **Apply the Right-Hand Thumb Rule**:
- The right-hand thumb rule is a convention used to determine the direction of angular displacement or angular velocity.

3. **Identify the Direction of Motion**:
- If the particle is moving in a clockwise direction, you will curl the fingers of your right hand in the direction of the particle's motion.

4. **Determine the Thumb Direction**:
- When you curl your fingers clockwise, your thumb will point inward, towards the center of the circle. This indicates that the angular displacement is directed into the plane of motion.

5. **Consider the Anticlockwise Direction**:
- Conversely, if the particle is moving in an anticlockwise direction, you will again curl your fingers of the right hand in the direction of the motion.

6. **Thumb Points Outward**:
- When curling your fingers anticlockwise, your thumb will point outward, away from the center of the circle, indicating that the angular displacement is directed out of the plane of motion.

7. **Conclusion**:
- In both cases (clockwise and anticlockwise), the direction of angular displacement is perpendicular to the plane of the circular motion.

### Final Answer:
- The direction of angular displacement when a particle is performing uniform circular motion is perpendicular to the plane of the circular path.