A bowling ball weighing 67.0 N initially moves at a speed of 4.80 m/s. How long must a force of 54.5 N be applied to the ball to stop it?
mg = 67 N.
m = 67/g = 67 / 9.8 = 6.84 kg. = Mass of ball.
a = Fap/m = -54.5 / 6.84 = -7.97 m/s^2. = acceleration of ball.
Vf = Vo + at = 0.
t = (Vf-Vo)/a.
t = (0-4.80) / -7.97 = 0.60 s.