Momentum Problems
1	A frictionless wagon going at 2.5 m/w is pushed with a force of 380-N and its speed increases to 6.2 m/s in 4.0 s What is its mass?
2	What braking force is needed to bring a 2200 kg car going 18 m/w to rest in 6.0 s?
3.	A 650-kg rocket speeds up from 440 m/s to 520 m/s in outer space. If the thrust of the engine is 1200-N, how long must the engine be fired?
4.	A pitcher throws a ball whose mass is 0.30 kg, bringing it from rest to a speed of 35 m/s. If the motion of his arm while holding the ball lasts 0.50 s, find
	a) The new momentum of the ball
	b) The impulse the pitcher applied to the ball
	c) The force the pitcher used in throwing the ball
5.	A 35-kg girl is standing on a 20-kg wagon that is standing still before she jumps off. If the wagon goes at 3.8 m/s, what is her velocity?
6.	The same 35-kg girl is now running at 5.2 m/s and jumps onto the same 20-kg wagon that is standing still. How fast will the wagon and the girl move?
7.	A 1.2-kg basketball traveling at 7.5-m/s hits the back of a 12-kg wagon and sticks, sending the wagon off in the original direction of travel of the ball. How fast is the wagon and basketball going?
8.	Another time the 1.2-kg basketball traveling at 7.5-m/s hits the back of a 12-kg wagon and bounces off at 3.8 m/s, sending the wagon off in the original direction of travel of the ball. How fast is the wagon going?