levers – is a tool to make lifting or moving something easier

(pronounced lee-vuh)

There are three classes of levers based on where the lever pivots.

First order (1) Effort then Fulcrum then Load (seesaw)

Second order (2) Effort then Load then Fulcrum (wheelbarrow)

Third order (3) Fulcrum then Effort then Load (tweezers)

To remember the order of the class of lever use the following mnemonic:

The seesaw (1) lifted a wheelbarrow (2) but it fell off and spilled a load of tweezers (3).

A first class lever has the fulcrum in the middle (e.g. a seesaw).

If the load is closer to the fulcrum it becomes easier to lift. Examples of first class levers include scissors, crowbars, rowing and a hammer used as a lever.

A second class lever has the load in the middle (e.g. a wheelbarrow).

Examples of a second class lever include nutcrackers, bottle openers and doors.

A third class lever has the effort in the middle (e.g. tweezers).

Exmples include fishing and using a spade.