Imagine that a child is inside a car traveling at 8 m/s.The child throws a ball with a velocity of 1 m/s in the direction of the car's motion.How fast is the ball traveling relative to an observer at rest on the side of the road?

Question

Quizplus · Accepted Answer

The ball's velocity relative to the car is 1 m/s, and the car's velocity relative to the observer on the side of the road is 8 m/s. Therefore, to find the ball's velocity relative to the observer, we need to add the two velocities using the formula for relative velocity:

Vrelative = Vobject  + Vobserver

Vrelative = 1 m/s + 8 m/s 
Vrelative = 9 m/s

So the ball is traveling at 9 m/s relative to an observer at rest on the side of the road. Therefore, the best choice is C) 9 m/s.

Imagine That a Child Is Inside a Car Traveling at 8