A pulley uses a wheel and a rope, cord, or chain. Pulleys help us lift things that are heavy. Here are some examples of pulleys at work.
Sailboats use pulleys. Pulleys help raise the sails, turn the boat, and more.
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Pulleys help us build. Cranes use pulleys. So do other construction machines.
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A rock climber wears a harness. It is attached to a person with a pulley. This helps keep the climber from falling if he or she slips.
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A ski lift takes people up ski slopes. It is made of many pulleys. One of them is huge! Take a look at it here.
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This is what a pulley looks like up close. Pulleys make it easier to lift heavy things. Can you think of other everyday examples of pulleys?