Lever Systems GCSE PE What is a lever

Lever Systems GCSE PE

What is a lever? In your body its how the muscles, bones and joints work together to create movement.

How does a lever work? A lever rotates around an axis A fulcrum (or pivot) – the point around which the lever rotates A load – the force that is applied by the lever system An effort – the force that is applied by the user of the lever system

First class lever

Second class lever

Third class lever

Why do we use levers? https: //www. youtube. com/watch? v=Yl. YEi 0 Pg. G 1 g

Mechanical advantage When the output of the lever is greater than the input. When the load is greater than the effort First and second class levers both work at mechanical advantage

Mechanical disadvantage When the effort and load are both on the same side of the fulcrum, but the effort is closer to the fulcrum The effort is greater than the load Third class levers work at mechanical disadvantage

Advantages / Disadvantages Fast or slow? Strong or weak? Does increasing the lever arm increase / decrease mechanical advantage? Range of motion?

Class of lever Advantage Disadvantage First class • Stable • Slow • Strong • Limited flexibility • Increasing the length of the lever increases mechanical advantage Second class • Stable • Slow • Strong • Limited flexibility • Increasing the length of the lever increases mechanical advantage Third class • Fast movement • Force applied must • Large range of always be more than motion the load • Increasing the length of the lever arm decreases