machines
a machine is a device that makes a physical task easier
eg: cars, cranes, escalators
simple machines
most machines are made up of many smaller machines called simple machines
there are 6 kinds of simple machines
lever, inclined plane, wedge, wheel and axle, pulley & screw
check out
http://atlantis.coe.uh.edu/archive/science/science_lessons/scienceles1/finalhome.htm
http://www.ee.nmt.edu/~tubesing/missionpossible/simplemachines.pdf
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Purple Patch 
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