Simple machines make work easier by multiplying, reducing, or changing the direction of a force. A lever is a type of simple machine. You can make one and experiment with how moving the pivot point, or fulcrum, changes the way the lever can lift things.
In this experiment, you took a basic ruler or piece of wood and added a fulcrum to make a simple machine called a lever! To understand how a lever works - picture a playground see-saw. With the heavier object on one end, the lighter (empty) end of the lever was raised up. By moving the fulcrum closer to the heavy end, you were able to use the lever to help you raise the heavier object when you placed a lighter one on the opposite end. This didn’t change anything about the lighter weight - it stayed exactly the same. Moving the lever’s pivot point closer to the object you were trying to lift changed how much force (or work) it took to lift the object. Moving the fulcrum closer to the object made it much easier to lift a heavy object. What do you think would happen if you moved the fulcrum the opposite direction? It would take more force, or in this example, a heavier weight to lift the object!
When talking about levers, things can get a little confusing, so there are a few terms we can use to help keep things straight. In our experiment above, the heavy object we were trying to lift is called the load force. The lighter weight we used to lift the load force is called the effort force. When the fulcrum was in the middle of the lever, the effort force had to be greater than the load force in order to lift the load force up. But, by simply changing the pivot point of the lever, we were able to use a smaller effort force to lift the greater load force. That is the beauty of levers - making work easier by lowering the amount of force that is required to lift or move something!
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