Interactive simulation of lever mechanics with torque balance, mechanical advantage, and three classes of levers
A lever is a simple machine consisting of a rigid beam pivoted at a fixed point (fulcrum). It allows you to lift heavy loads with less effort by trading force for distance. The principle of levers has been used for thousands of years in tools like scissors, pliers, and seesaws.
Torque (τ) is the rotational force that causes an object to rotate. It's calculated as the product of force and distance from the fulcrum (τ = F × L). A lever is balanced when the torques on both sides are equal: F₁ × L₁ = F₂ × L₂. When unbalanced, the lever will rotate in the direction of the greater torque.
Mechanical Advantage (MA) measures how much a lever multiplies the input force. It's calculated as MA = L₁ / L₂ (distance from fulcrum to effort divided by distance from fulcrum to load). An MA greater than 1 means the lever amplifies force, making it easier to lift heavy objects.
Fulcrum is between effort and load (e.g., seesaw, scissors). Can change force direction and provide mechanical advantage.
Fulcrum on one side with both forces on same side. Class 2 has load closer to fulcrum (mechanical advantage), Class 3 has effort closer (favors speed and distance). Adjust distance parameters to switch between them.