Find Force given mass, velocity and time

Question

A child bounces a 48 g superball on the sidewalk. The velocity change of the superball is from 25 m/s downward to 14 m/s upward. If the contact time with the sidewalk is 1 800 s, what is the magnitude of the average force exerted on the superball by the sidewalk? Answer in units of N.

Answer 1

The relationship between average force (F) and momentum (p) is

F = Δp/Δt = (p_f - p_i) / Δt

With p = mv, you should now have all the information you need to finish the problem.

Note: Don't forget to convert your mass to kilograms so your answer is in Newtons.