# A 0.70 kg ball moving horizontally at 5.0

A 0.70 kg ball moving horizontally at 5.0 m/s strikes a vertical wall and rebounds with speed 2.0 m/s. What is the magnitude of the change in its linear momentum?

#### Solution:

We can use the following equation to solve this problem.

$\Delta p=m\mid v_i-v_f\mid$

##### (Where $p$ is the momentum change, $m$ is mass, $v_i$ is initial velocity, and $v_f$ if final velocity)

Substitute the values given to us in the question:

$\Delta p=(0.7)\mid(5-(-2)\mid$

$\Delta p=4.9$ kg$\cdot$m/s

$\Delta p=4.9$ kg$\cdot$m/s