A girl throws a 0.1 kilogram ball at a wall. The ball hits the wall perpendicularly with a velocity of 5 meters per second and then bounces straight back with a velocity of 4 meters per second. The change in the momentum of the ball is:
a) 0.1 kilogram-meters per second
b) 0.4 kilogram-meters per second
c) 0.5 kilogram-meters per second
d) 0.9 kilogram-meters per second
Ans:
The change in the momentum of the ball is 0.9 kilogram-meters per second.