10217

# Three Classes of Levers

The lever is a simple machine that provides mechanical advantage to magnify the force necessary to overcome a resistance. Levers were known to the ancient Greeks, having been described by Archimedes in the Third Century BCE. Three classes of lever differ in their configuration of the fulcrum, load, and force, shown as a blue triangle, black weight, and red arrow, respectively. Class 1 levers have the fulcrum in the central position, with the force applied at one end to move the load at the other end in the opposite direction. Examples are scissors and pliers (actually both double levers), crowbars, claw hammers (when used to pull out nails), and seesaws. Class 2 levers have the load in the central position with the force at one end making it move the same direction around the fulcrum at the opposite end. Examples are the nutcracker (again a double lever) and wheelbarrow. Class 3 levers apply the force in the central position, again to impel the load in the same direction, for example, baseball bats, tennis rackets, human arms, tweezers, and doors.
In this Demonstration, you can choose one of the three classes of levers and simulate its operation. A real-life realization of each type is also illustrated.

### PERMANENT CITATION

 Share: Embed Interactive Demonstration New! Just copy and paste this snippet of JavaScript code into your website or blog to put the live Demonstration on your site. More details » Download Demonstration as CDF » Download Author Code »(preview ») Files require Wolfram CDF Player or Mathematica.

#### Related Topics

 RELATED RESOURCES
 The #1 tool for creating Demonstrations and anything technical. Explore anything with the first computational knowledge engine. The web's most extensive mathematics resource. An app for every course—right in the palm of your hand. Read our views on math,science, and technology. The format that makes Demonstrations (and any information) easy to share and interact with. Programs & resources for educators, schools & students. Join the initiative for modernizing math education. Walk through homework problems one step at a time, with hints to help along the way. Unlimited random practice problems and answers with built-in Step-by-step solutions. Practice online or make a printable study sheet. Knowledge-based programming for everyone.