Question

A ball of mass m = 241 g is heading towards a wall at 20.0 m/s. After the collision with the wall, it travels in the opposite direction with a speed of 16.0 m/s. The impact with the wall lasted 60.0 ms . What is the magnitude of the average force exerted by the wall on the ball during this time?

Answer 1

`F=144.6N`

Step-by-step explanation:

Newton's 2nd Law and the definition of acceleration tells us that:

`F=ma=m(\Delta v)/(\Delta t)=m(v_f-v_i)/(t)`

Taking the final direction of the ball as the positive direction, which would be the direction of the force the wall exerts (so it should be positive), for our values (in S.I.) we will have:

`F=m(v_f-v_i)/(t)=(0.241kg)((16m/s)-(-20m/s))/(0.060s)=144.6N`