Levers
A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or fulcrum. Levers are used to amplify an input force to provide a greater output force, which is said to provide leverage. There are three classes of levers, determined by the relative positions of the fulcrum, effort, and resistance.
Key Points
- Class 1: Fulcrum between effort and resistance (e.g., Seesaw, Crowbar).
- Class 2: Resistance between fulcrum and effort (e.g., Wheelbarrow, Bottle opener).
- Class 3: Effort between fulcrum and resistance (e.g., Tweezers, Fishing rod).
Formulas & Concepts
Lever Principle:Effort x Effort Arm = Resistance x Resistance Arm