Question

Which pair of sentences is describing the same velocity? A car is parked. A car is moving in circles. A bus drives 40 miles per hour north. A truck drives 50 miles per hour north. A boy walks east at 6 kilometers per hour. A girl walks west at the same speed as the boy. Valerie rides her bike south at 8 kilometers per hour. Owen jogs south at 8 kilometers per hour.

Answer 1

The bus and the truck have the same velocity.

Also, Valerie and Owen have the same velocity.

Answer 2

Velocity is a vector, so it contains two pieces of information:

- a magnitude, which is given by the speed

- a direction

Two objects, in order to have same velocity, should have both same speed and same direction. In this problem, only the following pair of sentences describe people with same velocity:

Valerie rides her bike south at 8 kilometers per hour.

Owen jogs south at 8 kilometers per hour.

In fact, both Valerie and Owen are moving at same speed (8 km per hour) in the same direction (south), so they have same velocity.