A bowling ball weighing 43.0 N initially moves at a speed of 4.90 m/s. How long must a force of 51.0 N be applied to the ball to stop it?

mg = 43 N.

m = 43/g = 43 / 9.8 = 4.39 kg = Mass of
ball.

a = Fap / m = -51 / 4.39 = -11.62 m/s^2

Vf = Vo + at = 0.
t = (Vf-Vo)/a.
t = (0-4.9) / -11.62 = 0.422 s.

NOTE: Fap = Force applied. Vf = Final
velocity. Vo = Initial velocity.