Name_________________________________ Block______________
Work, Power and Machines Test Review
Test Day_________________
Theory:
1. How is work defined? How is Power defined?
2. How do machines help us accomplish work?
3. What does mechanical advantage of a machine tell us? What is a good machine?
4. You lift a load up one flight of stairs. If Nellie Newton pushes an object an object with twice the force for twice
the distance, she does
5. What is the law of conservation of energy?
6. List the 6 simple machines. Give one example of each.
7. Draw the 3 classes of levers. Must know how to identify lever class on test.
1st Class:
2nd Class:
3 rd Class:
8. What does F, E, and R represent on a lever?
9. What are the units & symbol for each quantity? There will be a matching section on test.
Ex: Distance or displacement : d-meters
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mass
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Efficiency
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Any type of Force
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Mechanical advantage
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time
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Work
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Name_________________________________ Block______________
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Power
10. What are the 2 groups of machines? (See foldable)
11. What group does a pulley fall under? A wedge?
12. Label the pictures below as a first, second or third class lever.
Math: Please show formula, work, calculator and sig. fig answer.
13. Calculate the amount of work done when moving a 567 N crate a distance of 20 meters.
14. A) What is the weight of a 49 Kg crate? B) What work is done to lift the crate a vertical distance of 10
meters?
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Name_________________________________ Block______________
15. If it takes 68 joules of work to push a desk chair 2.5 meters across a floor, what force would be
needed?
16. What is the mechanical advantage of a lever that has an input arm of 2 meters and output arm of 10 meters.
17. A 10 meter long ramp has a mechanical advantage of 5. What is the height of the ramp?
18. What is the EFFICIENCY of an inclined plane that is 6.00 meters long and 1.00 meter high? The effort force is
2160 N and the resistant force is 10,000 N.
**Make sure you have all formulas on your work/machines chart. Practice ALL math questions on
review. 
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