Question

Does the odometer of a car measure a scalar or a vector quantity? What about speedometer?

Short answer

Both odometer and speedometer measure scalar quantities.

Step-by-step solution

Step 1. Definitions of scalar and vector quantities

• A physical quantity that has both direction and magnitude is called a vector quantity. For example, force, velocity, displacement.

• A physical quantity that has magnitude and no direction is called a scalar quantity. For example, distance, speed, pressure.

Step 2. Determining whether the odometer measures a vector or a scalar quantity

An odometer is a device that shows the total distance traveled by the vehicle. As distance is a scalar quantity, you can say that an odometer measures a scalar quantity.

Step 3. Determining whether the odometer measures a vector or a scalar quantity

A speedometer is a device that shows the instantaneous speed of the vehicle. As speed is a scalar quantity, you can say that a speedometer measures a scalar quantity.

Step 4. Obtaining the final solution

Hence, both odometer and speedometer measure scalar quantities.