In some types of work, pulling is easier than pushing. Sometimes the direction in which you are pulling has to be a little different than the direction that the load needs to be moved. In these cases, wheels and ropes can be used to change the direction of the effort that is used to move the load. These wheels and ropes used together are called a pulley. A pulley is a wheel that turns on an axle. The wheel has a groove in it. A belt or rope is placed around the wheel and sits in the groove. There are two basic types of pulleys - fixed and movable. A fixed pulley is fixed in place, attached to a stable structure. A flag pole usually uses a fixed pulley to move the flag up or down. Fixed pulleys may be used in warehouses to lift loads off of trucks or trains. A fixed pulley works by changing the direction of the force and allowing you to raise things above your head (such as a flag up a flagpole). However, fixed pulleys do not have any mechanical advantage. You must exert the same effort to lift an object on a fixed pulley as you would if you were to carry the object up yourself.
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Fixed Pully
How does a fixed pulley work?
A fixed pulley works by changing the direction of the force and allowing you to raise things above your head.
