Which one of the following quantities is a vector quantity ?

Options

A. the age of the earth
B. the mass of a freight train
C. the Earth's pull on your body
D. the temperature of hot cup of coffee

Answer

To determine which of the given quantities is a vector quantity, we need to understand the definitions of vector and scalar quantities.

### Step-by-Step Solution:

1. **Understanding Vector and Scalar Quantities**:
- A **vector quantity** has both magnitude and direction. Examples include displacement, velocity, and force.
- A **scalar quantity** has only magnitude and no direction. Examples include mass, temperature, and time.

2. **Analyzing the Options**:
- **Option 1: Age of the Earth**:
- Age is measured in years (a magnitude) but does not have a direction. Therefore, it is a scalar quantity.
- **Option 2: Mass of Freight Train**:
- Mass is a measure of the amount of matter in an object (a magnitude) and does not have a direction. Hence, it is also a scalar quantity.
- **Option 3: Earth Pull on Your Body**:
- The gravitational pull (force) exerted by the Earth on your body has both magnitude (the weight of the body) and direction (towards the center of the Earth). Therefore, this is a vector quantity.
- **Option 4: Temperature of Hot Cup of Coffee**:
- Temperature is a measure of thermal energy (a magnitude) and does not have a direction. Thus, it is a scalar quantity.

3. **Conclusion**:
- Among the given options, the only quantity that is a vector quantity is the **Earth pull on your body**.

### Final Answer:
The Earth pull on your body is a vector quantity.

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