Question

A beach ball is rolling in a straight line toward you at a speed of 0.5 m/s. Its momentum is 0.25 kg*m/s.

What is the mass of the beach ball?

Answer 1

Given:

$v=0.5\:\rm m/s$

$p=0.25\:\rm kg*m/s$

The momentum of a ball is given by

$$p=mv$$

Hence, the mass of the ball

$$m=p/v=\rm 0.25\: kg*m/s/0.5\: kg=0.5\: kg$$