Question

What is the speed of a 6-kg ball with a momentum of 72 kg∙m/s?

Answer 1

The momentum of a moving object is given by:
$p=mv$
where m is the mass of the object and v its speed.

In this problem, the ball has a mass of $m=6 kg$ and its momentum is $p=72 kg m/s$, so we can rearrange the previous equation to find the speed of the ball:
$v= \frac{p}{m}= \frac{72 kg m/s}{6 kg}=12 m/s$