High School physics

Question

Adam is riding forward on an electric scooter at 10 m/s. He throws a ball to Robert, who is stationary. The ball travels at a speed of 8 m/s relative to Adam. How fast is the ball moving relative to Robert as he tries to catch it?



A.18 m/s

B.10 m/s

C.8 m/s

D.2 m/s

Answer 1

I assume that Adam throws the ball in the same direction that the scooter is moving. Then the speed of the ball relative to Robert must be

 

10 m/s + 8 m/s = 18 m/s