Which of the following physical quantities is an axial vector ?

Options

A. displacement
B. force
C. velocity
D. torque

Answer

To determine which of the following physical quantities is an axial vector, we need to understand the definition and characteristics of axial vectors.

### Step-by-Step Solution:

1. **Understand Axial Vectors**:
- An axial vector, also known as a pseudovector, is a vector that represents the rotational effect of a force. Its direction is perpendicular to the plane formed by the two vectors involved in the cross product that defines it.
- Common examples of axial vectors include torque and angular momentum.

2. **Identify the Options**:
- Although the options are not provided in the question, typical candidates for physical quantities might include:
- Torque
- Force
- Displacement
- Velocity

3. **Analyze Each Option**:
- **Torque**: Torque is defined as the cross product of the position vector (r) and the force vector (F), represented as τ = r × F. The direction of torque is along the axis of rotation, making it an axial vector.
- **Force**: Force is a vector quantity that acts in the direction of the applied force. It is not an axial vector.
- **Displacement**: Displacement is a vector quantity that indicates the change in position. It is not an axial vector.
- **Velocity**: Velocity is a vector quantity that indicates the rate of change of displacement. It is not an axial vector.

4. **Conclusion**:
- Based on the analysis, the only quantity that qualifies as an axial vector is **Torque**.

### Final Answer:
The correct option is **Torque** (Option D).

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