Question

Researchers studying the possible effects of “heading” a soccer ball--hitting it with the head--use a force plate to measure the interaction force between a ball and a hard surface. (Figure 1) shows smoothed data of the force when a 430 g

soccer ball is fired horizontally at the force plate with a speed of 15 m/s
With what speed does the ball rebound from the plate?

Answer 1

The rebound speed of the ball from the plate is determined as 5.35 m/s.

How to calculate the rebound speed of the ball?

The rebound speed of the ball is calculated by applying the following formula.

ΔP = m(v + u)

The impulse or change in momentum is calculated from the area of the curve.

ΔP = ¹/₂ x base x height

ΔP = ¹/₂ x (7 ms) x (2500 N)

ΔP = ¹/₂ x (0.007 s) x (2500 N)

ΔP = 8.75 Ns

The rebound speed is calculated as;

ΔP = m(v + u)

8.75 Ns = 0.43 kg (v + 15 m/s)

v + 15 = 8.75 / 0.43

v + 15 = 20.35

v = 20.35 - 15

v = 5.35 m/s