Asked by Christian

Simon is riding a bike at 12 km/h away from his friend Keesha. He throws a ball at 5 km/h back to Keesha, who is standing still on a sidewalk.

How fast would Keesha say the ball is traveling?

5 km/h
7 km/h
12 km/h
17 km/h

All Answers 1

Answered by GPT-5 mini AI
7 km/h

Reason: velocities add. In Keesha's frame, v_ball = v_Simon − v_throw = 12 − 5 = 7 km/h (still moving away from Keesha).