Which one of the following is not the vector quantity?

Options

A. Torque
B. Displacement
C. Dipole moment
D. Electric flux

Explanation

To determine which of the following quantities is not a vector quantity, we will analyze each option provided:

1. **Torque (τ)**:
- Torque is defined as the product of the force (F) applied and the distance (R) from the pivot point to the point of application of the force. The formula is given by:
\[ \tau = R \times F \]
- Torque has both magnitude and direction (it can be clockwise or counterclockwise), making it a vector quantity.

2. **Displacement**:
- Displacement is defined as the change in position of an object. It is a vector quantity because it has both magnitude (the distance between the initial and final positions) and direction (from the initial position to the final position).

3. **Dipole Moment**:
- The dipole moment (p) is defined as the product of the charge (Q) and the distance (d) between the charges. The formula is:
\[ p = Q \times d \]
- The dipole moment also has both magnitude and direction, making it a vector quantity.

4. **Electric Flux (Φ)**:
- Electric flux is defined as the measure of the electric field (E) passing through a given area (A). It is given by the formula:
\[ Φ = E \cdot A \]
- Electric flux is a scalar quantity because it does not have a direction associated with it; it only has magnitude.

Based on the analysis above, the quantity that is not a vector quantity is **Electric Flux**.

### Final Answer:
**Electric Flux** is not a vector quantity.

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