Question

What average net force is required to stop a 3.5 kg bowling ball initially travelling at a speed of 1.5 m/s over a distance of 0.4 m?

Answer 1

First the aceleration:

Vf² = Vo² - 2ad

a = (Vf² - Vo²) / 2d

a = (0 m/s)² - (1,5 m/s)²) / 2 * 0,4 m

a = -2,25 m²/s² / 0,8 m

a = -2,81 m/s²

Now, for the net force, use 2nd law of Newton:

F = ma

F = 3,5 kg * (-2,81 m/s²)

F = -9,835 N

The force for stop the bowling ball is -9,835 Newtons.