Problem 56.

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

Solution:

The odometer of the car shows the magnitude of the vector quantity.

The odometer shows the speed of the car.

The speed of the car is the magnitude of the velocity (which is the vector) of the car.

So the odometer gives us only the number, it does not show us the direction of velocity. The odometer measure the scalar quantity – the speed of the car.