The LeverHome Page | The Inclined Plane | The Lever | Bibliography The lever is a rigid rod that is supported at one point, known as the fulcrum. The lever consists of three classes: Class 1, Class 2, and Class 3.
Fulcrum or pivot - the point about which the lever rotates
Load - the force applied by the lever system
Effort - the force applied by the user of the lever system
Class 1 levers have the fulcrum in between the effort and the load. By adjusting how far the fulcrum is from the load, you can control the mechanical advantage.
Examples of Class 1 Levers:
The Teeter-Totter
The Crow Bar
A Pair of Scissors
The class one lever has a mechanical advantage of one.
Class 2 levers have the load between the effort and the fulcrum. The wheel's axle is the fulcrum, the person lifting the handles puts in the effort, and the load is between them
Examples of Class 2 Levers:
The Wheel Barrow
A Bottle Cap Opener
A Nut-Cracker
The class two lever has a mechanical advantage of one.
Class 3 have the effort between the load and the fulcrum. A hammer acts as a class 3 lever when it is used to drive in a nail: the wrist is the fulcrum, the effort is applied through the hand, and the load is the resistance of the wood. Examples of Class 3 Levers:
A Hockey Stick
Tweezers
A Baseball Bat
A Human Arm
The class three lever has a mechanical advantage of less than one.
The lever is a rigid rod that is supported at one point, known as the fulcrum. The lever consists of three classes: Class 1, Class 2, and Class 3.
Examples of Class 1 Levers:
The class one lever has a mechanical advantage of one.
Examples of Class 2 Levers:
The class two lever has a mechanical advantage of one.
Examples of Class 3 Levers:
The class three lever has a mechanical advantage of less than one.
Some Explanatory Videos:
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