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```PHYSICS
Chapter 6 - Momentum & Collisions
Worksheet #1
Name____________________
1. Calculate the momentum of a 0.65-kg gumball traveling at 28 m/s. 18.2 kg m/s
2. The momentum of an 8.6 kg ball is 132 kg.m/s. What is the velocity of this ball? 15.3 m/s
3. A 80 kg man is running at 9 m/s and a 1200 kg car is moving at 1.5 m/s.
a. Which has more momentum - the man or the car? car
b. Which has more kinetic energy - the man or the car? man
4. A 900 kg car changed its speed from 12 m/s to 18 m/s. What was the car's change of momentum? 5400 kg m/s
5. A boy on a skateboard slowed from 13 m/s to7 m/s. The-mass of the boy and his board is 65 kg. What
was the change of momentum involved? -390 kg m/s
6.A force of 40 N acts on a 8 kg box of saltines for 7 seconds. What was the impulse given to this box?
260 N s
7. A 75 N*s impulse is given to a 12 kg box over a period of 15 seconds. What force was applied to this
box? 5 N
8. A 2000 kg car is rolling along the highway at 8 m/s. A braking force of 500 N is applied to stop the
car. What length of time will it take to bring the car to a rest? 32 s
9. If a 84 N*s impulse is given to a 4 kg object, the change of momentum of the object is what?
84 kg m/s
10. A force of 50-N acts on a 7-kg object for 8 seconds.
a. What is the impulse acting on this object'? 400 N s
b. What is the object's change of momentum? 400 kg m/s
c. What is the object’s change in velocity? 57.1 m/s
d. What is the rate at which the object is being accelerated? 7.14 m/s2
e. How far does the object travel during the 8 second period of time (assume the object started at
rest)? 229 m
11. A car of mass 900 kg is moving at 25 m/s. A force of 500 N acts upon the car to bring it to a halt.
a. What is the car's initial momentum? 22500 kg m/s
b. What is the car's final momentum? 0 kg m/s
c. How long (time}-does it take the braking force acting on the car to bring the car to a halt? 45 s
12. A force of 40 N acts on a 5 kg cart for 6 seconds.
a. What is the impulse this force exerts on the cart? 240 N s
b. If the cart was initially at rest, what will be its velocity at the end of the 6 seconds? 48 m/s
c. How far will the cart travel in those 6 seconds? 144 m
d. What force would now be required to cause the cart to come to a halt in the next 10 seconds?
24 N
13. A ball of mass 30 grams is traveling along a line at the rate of 16 m/s. This ball overtakes and
collides with a 20 gram ball also traveling in the same direction along the same line with a velocity of 6
m/s. After the collision, the first ball continues to move along the line in its original direction at the rate
of 4 m/s. What will be the velocity of the second ball (20 grams) after the collision? Note the unit of the
ball’s mass. 24 m/s
14. A cannon with a mass of 800 kg fires a shell with a mass of 6 kg at a rate of 750 m/s. What is the
recoil velocity of the cannon? -5.62 m/s
15. A 4-kg object moving with a velocity of 8 m/s to the right collides with a 10-kg object moving with
a velocity of 3 m/s to the left. Find the velocity of the 10-kg object if the 4 kg object rebounds the left at
3 m/s. (Assume all motion is along a straight line path.) 1.4 m/s to the right
``` # Solutions to Practice Exam 2 1. Initially we have a system (machine 