Name: __________________________________________ Period: ___ Date: _________

Dekalb Reads Assignment  9.2 A

Simple Machines

1. Define simple machines.
2. All machines are either modification or combination of _______________________________ .
3. Name the two families of simple machines.
4. Which part of the claw hammer does work on the nail?

Look at the diagrams in figure 9-5 and answer #5-13.

5. What kind of lever is shown in diagram ‘A’?
6. Where is the fulcrum situated in first class lever?
7. Where are the output and input forces situated in the first class lever?
8. Where is the fulcrum situated in the 2^nd class lever?
9. Where is the output force situated in the 2^nd class lever?
10. Where is the input force situated in the first class lever?
11. Where is the fulcrum situated in the 3rd class lever?
12. Where is the output force situated in the 3rd class lever?
13. Where is the input force situated in the 3rd class lever?
14. Give an example of first class lever.
15. Give an example of 2^nd class lever.
16. Give an example of 3^rd class lever.
17. What is fulcrum?
18. What happens to the original input force in the lever?
19. What kind of lever are pliers?
20. What kind of lever is a hinged door?
21. Pulleys are ___________________________________ .
22. What kind of lever is a pulley?
23. What is the Mechanical Advantage (MA) of a single fixed pulley?
24. Multiple pulleys are sometimes put together in a single unit called ______________________ .

Look at figure 9-6 and answer the questions 25-27.

25. What is the Mechanical advantage of a single moving pulley?
26. What is the Mechanical advantage of a pulley system having a moving and a fixed pulley?
27. If the output force is 150 N and MA is 3, what will be the input force?