Question

A soccer ball with a mass of 0.60 kg travels toward a soccer goalie at

Answer 1

Assuming constant acceleration, the goalie slows the ball from 18 m/s to rest in 0.035 s, so that the acceleration felt by the ball is

$a_{\rm ave} = a = \dfrac{18\frac{\rm m}{\rm s}-0}{0.035\,\mathrm s} \approx \boxed{510\dfrac{\rm m}{\mathrm s^2}}$