Download SCCS Physics Chapter 11 Study Guide Name

SCCS Physics Chapter 11 Study Guide
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1. State the law of conservation of energy. What are some examples of different forms of energy?
Describe a process that converts one form of energy to another.
2. What is GPE? What factors increase or decrease GPE?
3. What is mechanical energy? How is it related to KE and GPE?
4. What is elastic PE? Give an example of an object that stores elastic PE.
5. What does it mean if a system is “closed”? What does it mean if a system is “isolated”?
6. What is an elastic collision? Describe two objects that collide elastically.
7. What type of object would experience inelastic collisions?
8. Energy is measured in what kind of units? Is this true for all types of energy?
9. When a moving object comes to rest, what has happened to the kinetic energy of the object?
10. Describe an object that has rotational KE but no translational KE.
11. Describe an object that has translational KE but no rotational KE.
12. At what point in a pendulum’s swing are the the following quantities at maximum values?
a) velocity b) potential energy c)kinetic energy
PROBLEMS: (Draw a diagram. Write out all equations, using only variables. Do not put in numbers yet.
Assign variables to all given values. Solve for the unknown value)
1. A 3.0-kg block starts at rest at the top of a 37° incline, which is 5.0 m long. Its speed when it reaches the
bottom is 2.0 m/s. What is the average friction force opposing its motion?
2. A student lifts a 1.2-kg bag from her desk, which is 0.59-m high, to a locker that is 2.9-m high. What is the
gravitational potential energy of the bag relative to the desk?
3. A 2.90  103 -kg bullet is fired with a velocity of 154 m/s toward a 5.44-kg stationary solid block resting on
a surface that has a coefficient of friction 0.215. The bullet emerges with a reduced velocity of 20.2 m/s after
passing through the block. What distance will the block slide before coming to rest? Assume that the block does
not lose any mass.
4. Erin holds the 1.20-kg bob of a pendulum at a level at which its gravitational potential energy is 3.00 J, and
then releases it.
a.
Predict the speed of the bob as it passes through its lowest point on the swing.
b.
Erin releases the bob from rest and uses a photogate to measure its speed as it passes
through its lowest point. She finds that the actual speed is 93.2 percent of the predicted value. How
much work did frictional forces do on the pendulum?
c.
By what percentage was the pendulum’s original energy decreased due to the work done
by frictional forces on the pendulum as it moved from its release point to its lowest point?