pulleys alex
Post on 30-May-2015
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Alex nyhof
What is a pulley?
A pulley is a wheel & a endless rope. Like an elevator.
When, why, who?
Pulleys were made along time ago. They could have been made in 250 BC! Why the pulley was made is to lift heavy objects to high places. A crane has a pulley & a lever but we are talking about pulleys.
Different kinds
A pulley can also have two wheels! The two wheel pulley it is easier to lift heaver objects. A one wheel pulley is harder to lift heaver objects.
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