Speedometer of a car measures

Options

A. average speed
B. average velocity
C. instantaneous speed
D. instantaneous velocity

Explanation

To solve the question regarding what the speedometer of a car measures, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Speed and Velocity**:
- Speed is a scalar quantity that refers to how fast an object is moving, regardless of its direction.
- Velocity, on the other hand, is a vector quantity that includes both speed and direction.

2. **Differentiating Average and Instantaneous Speed**:
- **Average Speed**: This is calculated by taking the total distance traveled divided by the total time taken. It gives an overall speed for the entire journey.
- **Instantaneous Speed**: This is the speed of an object at a specific moment in time. It can change from one moment to the next.

3. **Function of a Speedometer**:
- A speedometer is an instrument in a vehicle that measures how fast the vehicle is moving at any given moment.
- It does not calculate average speed over a distance but rather provides a real-time reading of the vehicle's speed.

4. **Conclusion**:
- Since the speedometer displays the speed at any instant, it measures **instantaneous speed**.

### Final Answer:
The speedometer of a car measures **instantaneous speed**.

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