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Third-Class Levers in the Human Body
A lever is a type of simple machine where a rigid arm is arranged around a fixed point or fulcrum. Input, the force you put in, directed into an output force. The classic example of a lever is a seesaw. The fulcrum is in the middle, and when you push down on your side of the seesaw (input), it makesthe person on the other side of the seesaw go up (output).
There are three main classes of levers.Ifthe fulcrum is in the between the output force and input force as in the seesaw, itis a first-class lever.In a second-class lever, the output force is inbetween the fulcrum and the input force. An example of a second class lever is a wheelbarrow. The fulcrum is the wheel, the load of stuff in the wheel barrowrequires theoutput forceto be lifted, and the person at the handle supplies the input force. In a third-class lever, the input force is inbetween the output force and thefulcrum.An example of this class of leveris a baseball bat. The handle of the bat is the fulcrum, you supply the input force near the middle, and the other end of the bat that pushes the ball with the output forces. In a third-class lever, the input forceis greater than the output force but the output load is able to move farther.
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