Question

A ball of mass $0.5kg$ moving with speed of $2.0m/s$ strikes a rigid wall in a direction perpendicular to the wall and is reflected back after a perfectly elastic collision. If the ball has remained in contact with the wall for $0.5s$, calculate the average force exerted on the ball by the wall.

Answer 1

After reflecting back the change in momentum is nothing but $2\times \text{initial momentum}$ =$2\times 0.5Kg\times 2m/s=2Kgm/s$

Average force exerted is $\frac{\text{change in momentum}}{\Delta t}$

Given that $\Delta t=0.5s$

so by putting above value we get $Force=4N$