A lever is a simple machine that consists of a rigid bar supported at one point, known as the fulcrum. A force called the effort force is applied at one point on the lever in order to move an object, known as the resistance force or load, located at some other point on the lever. A lever is a simple machine that makes work easier for use; it involves moving a load around a pivot using a force. Many of our basic tools use levers, including scissors (2 class 1 levers), pliers (2 class 1 levers), hammer claws (a single class 1 lever), nut crackers (2 class 2 levers), and tongs (2 class 3 levers).
 A Type 1 Lever. |
 A Type 2 Lever. |
 A Type 3 Lever. |
A Type 1 Lever. |
Examples
of common tools (and other items) that use a type 1 lever include:
| Item | Number of Class 1 Levers Used | |
|---|---|---|
| see-saw |  |
a single class 1 lever |
| hammer's claws |  |
a single class 1 lever |
| scissors |  |
2 class 1 levers |
| pliers |  |
2 class 1 levers |
A Type 2 Lever. |
Examples
of common tools that use a type 2 lever include:
| Item | Number of Class 2 Levers Used | |
|---|---|---|
| stapler |  |
a single class 2 lever |
| bottle opener | a single class 2 lever | |
| wheelbarrow |  |
a single class 2 lever |
| nail clippers | Two class 2 levers | |
| nut cracker | Two class 2 levers | |
A Type 3 Lever. |
Examples
of common tools that use a type 3 lever include:
| Item | Number of Class 3 Levers Used | |
|---|---|---|
| fishing rod |  |
a single class 3 lever |
| tweezers | Two class 3 levers | |
| tongs |  |
Two class 3 levers |