Question

A ball of mass 0.5 kg, initially at rest, acquires a speed of 4 m/s immediately after being kicked by a force over a period of time 2 sec. What is the magnitude of the force?


1 N

0.5 N

2 N

4 N

Answer 1

a = 4m/s / 2s = 2m/s^2
F = ma

Answer 2

Or:
force * time = change of momentum
F * 2 = 0.5 * 4