Simple Machines-levers in the Human Body continued

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What type of lever is this?

Third order lever.
Is this the best type of lever to use for the shin? Yes. Explain.

To maximize movement this is the ideal lever. With the effort close to the fulcrum we can multiply the distance the load travels. Notice how the thigh muscle is attached just below the knee joint. Small changes in muscle length result in large changes in the distance traveled by the load.

The thigh muscles are a very strong group of muscles. A third order lever gives no mechanical advantage and therefore strong muscles are needed to generate significant forces resulting in leg movement.

Levers In the Human Body continued
The picture on the right shows the bone structure of the leg. Sitting down on a chair raise your shins to a horizontal position. Your thigh muscle tenses in order to lift the lower part of the leg. Using the shin as an example identify the fulcrum, load and effort. What type of lever is this? Is this the best type of lever to use for the shin? Explain. Solution
Redesign this lever to be a force multiplier.
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