A 86.0 kg diver falls from rest into a swimming pool from a height of 6.3 m. It takes 1.44 s for the diver to stop after entering the water. Find the magnitude of the average net force exerted on the diver during that time.

1 answer

Vf^2 = Vo^2 + 2g*d,
Vf^2 = 0 + 19.6*6.3 = 123.48,
Vf = 11.1 m/s.

a = (Vf - Vo) / t,
a = (0 - 11.1) / 1.44 = - 7.72 m/s^2.

Fn = ma = 86 * (-7.72) = -664 N. in
opposite direction.