.Physics 9
Name: _______________________
Chapter 3 Study Guide
Period: _____
Date________
1. A bullet is shot into a log (on a frictionless surface). The bullet has a mass of 0.050 kg and is
moving at 950 m/s before it hits the log. The log is initially at rest and has a mass of 5.00 kg. The
bullet sticks in the log. What speed will the log and bullet have afterward?
(4 pts) 3a
2. A ball was kicked into the air. At point A, the ball has a potential energy of 959 J and kinetic energy
of 441 J. At point B, it has a kinetic energy of 620 J. Determine its potential energy at point B. Ignore
friction and show work.
(2 pts) 3b
3.
Using the concept of conservation of energy, calculate the maximum velocity a 4.0 kg ball
will reach just before it hits the ground if it’s maximum height was 6 m. (3 pts)
4.
A 67 kg block is dropped off a cliff that is 38 m high. Determine the following:
(4 pts)
a. The potential energy of the block at the top
of the cliff:
Chapter 3 Study Guideanswers.docx
b. The kinetic energy of the block when it’s
speed is 21 m/s:
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6.
Calculate how long it takes to stop a 405 kg cart rolling on a flat surface at a speed of
2.8 m/s over using a force of 350 N.
(3 pts)
\7. A kid on a bike has momentum of 660 kg m/s. If the kid and the bike have a combined
mass of 120 kg, what is the kid’s velocity?
(2 pts)
8. Sarah slams her hand against a volleyball using 98 N of force. Identify the reaction force and
magnitude.
(1 pt)
9. A 1.5-kg coconut falls out of a tree from a height of 12 meters. Determine the coconut’s
potential and kinetic energy at each point shown in the picture. Its speed is zero at point A.
(5pts)
Etotal
EP
EK
A
B
C
D
E
10. The impulse necessary to change the momentum of a 50-kilogram object by 8 kg·m/sec is
11. Allie, who weighs 58 kilograms, is roller blading on a level surface. If she is rolling at 12
meters per second, to what height would she roll up an incline before stopping? (Assume there
is no friction.)
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12. Evan rolls a 6.8-kilogram bowling ball so slowly that it stops before it moves through all of
the pins. The impulse necessary to stop this bowling ball rolling at 1.5 meters per second is:
13. Stevie is pushing his younger sister, Sally, on a swing. If Sally has a mass of 28 kg, how
much higher above the ground must Stevie push her to increase her potential energy by 489
joules?
14. A volleyball player who weighs 620 newtons jumps 0.55 meters vertically off the floor.
What is her kinetic energy the instant before hitting the floor?
15. The momentum of a 2500 kilogram car traveling at 15 meters per second is:
16. A boy whose mass is 45 kilograms runs at 4.4 meters per second and jumps onto a 8kilogram stationary sled. The boy slides on the sled over a horizontal, frictionless surface at a
speed of:
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17. If a 3.3 kg model rocket was traveling from its “launch pad” at a speed of 51 meters per
second, 1.9 kg of gases would be expelled from the model rocket at a speed of about:
18. Calculate the work done to lift a wooden board weighing 58 newtons a distance of 1.4
meters.
19. What braking force is needed to stop a 10,000-kilogram car moving at 6 m/sec in a time of
2 seconds?
Know/understand/be able to explain/use the following:
• Newton’s Third Law of Motion
• Momentum
• Impulse
• Conservation of Momentum
• Energy (including Kinetic and Potential)
• Work
• Conservation of Energy
• Collisions (Elastic and Inelastic)
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