Name: Date: Class:
Ch. 13 "Work, Power, and Machines" Test Review Sheet
1. What is work?
2. What is the unit used to measure work?
3. A man pushes a box with a force of 20 N over 2 m, how much work does the man perform?
4. The brakes on a car exert a frictional force of 6000 N and 120,000 J. How many meters does it take the car to stop?
5. A child pulls a sled up 10 m up a hill using 500 J of work, how large of a force did she exert on the sled?
6. What is power?
7. What is the unit used to measure power?
8. A cars engine works at 150,000 W for 2 s. How much work does the car’s engine do in this interval of time?
9. A weight lifter does 200 J of work in 4 seconds. What is the power of the weight lifter?
10. What are 3 ways machines help us do work?
11. Name the 6 simple machines. Indicate which are in the lever family and which are in the incline plane family.12. Name and draw a picture of the three types of levers.
13. Name and draw a picture the three types of pulleys.
14. Give an example of the following machines:
- 1st class lever
- 2nd class lever
- 3rd class lever
- fixed pulley
- movable pulley
- block and tackle pulley
- wheel and axle
- inclined plane
- wedge
- screw
15. What is a compound machine?
16. Give an example of a compound machine.
17. What is mechanical advantage?
18. What is the unit for mechanical advantage?
19. A steering wheel has a MA of 90 and an effort force of 20 N. What is the resistance force of the steering wheel?
20. Determine the mechanical advantage of a automobile jack that lifts a 2000 N car using 10 N of force.
21. A man pulls 2 m of rope (effort distance) through a pulley to raise a weight. If the mechanical advantage of the axe is 1, how high will the weight rise?