Aball of mass 4.5 kg moving with speed of 2.2 m/s in the +x-direction hits a wall and bounces back with the same speed in the x direction. what is the change of the momentum of the ball?

The change of the momentum of the ball is

Explanation:

We should find (1)with the initial momentum and the final momentum. Linear momentum is defined as , using that on (1):

(2)

It's important to note that momentum and velocity are vectors and direction matters, so if +x direction is the direction towards the wall and the -x direction away the wall and so (2) becomes:

hypothesising or postulating