Professor Beaker's Learning Labs

Question: What is a lever?

A lever is a simple machine. A lever bar exerts a force to move a load by turning on a pivot or fulcrum.

When the fulcrum is located close to the load, a small force applied to the end of the lever bar farthest away from the fulcrum is magnified so that the lever bar easily moves the heavy load. The force is magnified when the long part of the lever bar moves through a great distance. The short part of the lever bar, located between the fulcrum and the load, moves through a much smaller distance.

There are three types of levers: 1st Class, 2nd Class, and 3rd Class. The relative position of the load, fulcrum and force determine the class of lever.

Classes of levers

    1st Class Lever                  2nd Class Lever                3rd Class Lever

plierswheel barrowFishing rod

Professor Beaker's Learning Lab about Levers: Simple Machines

Return to Science facts for kids page.

Email to Prof Beaker
For more information email:
This page last updated on: June 3, 2000
Page created by Eric Fyon
Website created by: Watson Information Services
© 1999 Andy Fyon