Objectives
1. Define work.
2. Calculate the amount of work done by a force.
3. Understand that the amount of work done does not depend on the path taken when
done against gravity.
8.2 Power
4. Define power and describe it's relationship to work.
5. Calculate the power of a given system.
8.3 Mechanical Energy; 8.4 Potential Energy; 8.5 Kinetic Energy
6. State the differences between mechanical energy, potential energy, and kinetic energy.
7. Calculate the gravitational potential energy of a system.
8. Calculate the kinetic energy of a moving object.
9. Give examples of situations in which the gravitational potential energy of an object
changes.
10. Give examples of situations in which the gravitational potential energy does not
change even though something is moved.
11. Describe how the kinetic energy of an object depends upon the speed of the object.
8.6 Conservation of Energy
12. State the law of conservation of energy.
13. Solve problems using the law of conservation of energy.
8.7 Machines
14. Define machine.
15. List the six simple machines.
16. Describe the function of a lever.
17. Give examples of situations in which the mechanical advantage of a machine is
a. greater than 1
b. less than 1
18. Calculate the mechanical advantage of a simple machine.
8.8 Efficiency
19. Explain why no machine can have an efficiency of 100%.
20. Calculate the efficiency of a simple machine.
Misconceptions
Note: The following statements are all FALSE!!!
1. Momentum and kinetic energy are much the same concept.
2. Energy is conserved only under certain conditions.
3. It is possible to get more energy out of a machine that is put in.