Which of the following is a vector quantity ?

Options

A. Mass
B. Quantity of heat
C. Small angle
D. Time

Answer

To determine which of the following quantities is a vector quantity, we need to analyze each option provided: mass, quantity of heat, small angle, and time.

### Step-by-Step Solution:

1. **Understanding Vector and Scalar Quantities**:
- A vector quantity has both magnitude and direction.
- A scalar quantity has only magnitude and no direction.

2. **Analyzing Each Option**:
- **Mass**:
- Mass is a measure of the amount of matter in an object. It is a scalar quantity because it only has magnitude (e.g., 5 kg) and no direction.
- **Quantity of Heat**:
- The quantity of heat refers to thermal energy transfer. It is also a scalar quantity since it has magnitude (e.g., 100 J) but no direction.
- **Small Angle**:
- An angle can be described in terms of its magnitude (e.g., 45 degrees) and can also indicate direction (e.g., clockwise or counterclockwise). Therefore, it has both magnitude and direction, making it a vector quantity.
- **Time**:
- Time is a measure of duration. It is a scalar quantity as it only has magnitude (e.g., 5 seconds) and no direction.

3. **Conclusion**:
- Among the options given, the only vector quantity is the **small angle**.

### Final Answer:
The vector quantity among the options is **small angle**.

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