Levers

A lever is a simple machine that consists of a rigid bar that pivots around a fixed point called the fulcrum. It is used to lift or move loads with less effort.

The three classes of levers are: 1) First-class lever (fulcrum in the middle), 2) Second-class lever (load in the middle), 3) Third-class lever (effort in the middle).

IMA = Length of effort arm / Length of load arm.

The IMA of a first-class lever can vary depending on the position of the fulcrum, effort, and load.

The IMA of a second-class lever is always greater than 1, as the effort arm is longer than the load arm.

The IMA of a third-class lever is always less than 1, as the load arm is longer than the effort arm.

A seesaw is an example of a first-class lever, where the fulcrum is in the center.

A wheelbarrow is an example of a second-class lever, where the load is between the effort and the fulcrum.

A pair of tweezers is an example of a third-class lever, where the effort is applied between the load and the fulcrum.

IMA represents the ideal mechanical advantage, which is the maximum possible advantage without considering friction or other losses.