http://mocomi.com/ presents: Wheel and Axle - Simple Machines
When we have to move a real heavy load, we have to use a great deal of force to push it, because of:
Frication: Force resisting the motion of the object on the ground.
Gravitational force: Force that pulls the object to the ground.
The “Wheel and axle” solves this problem in jiffy!
Learn about this simple machine, and see how it reduces the effort required to move certain objects through this fun and animated learning module.
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