Class 2 and 3 levers

[herring146]

A student of mine keeps wondering what a class 2 and 3 lever. Can someone please explain what the differences and usages of them are? Thanks in advance.

[Nydauron]

A student of mine keeps wondering what a class 2 and 3 lever. Can someone please explain what the differences and usages of them are? Thanks in advance.

Both second- and third-class levers have the fulcrum at the end of the beam. With a second-class lever, the force of work is applied at the other end of the beam while the load is located between the fulcrum and the point of force. This gives an MA > 1 and is typically used to lift heavier things (e.g. a wheelbarrow or a car jack, in its most basic form, involves a class 2 lever).

A third-class flips both positions of the load and force of work such that the load is at the end of the beam and the force of work is in between the fulcrum and the load. Third-class levers are typically used to lift things faster/hold things of lighter weight since the MA < 1 (e.g. fishing pole, tongs/tweezers).