Levers and moment of force – equilibrium about a pivot

Integrated ScienceForces & MotionAges 13–14

The lever's pivot can sit at the centre (a seesaw or balance) or at one end (a wheelbarrow). Drag the two forces along the bar to change the lever arms d₁ and d₂; the bar tilts toward the side with the larger moment, balancing when F₁·d₁ = F₂·d₂. The moment on each side, the force needed for balance, and the mechanical-advantage conclusion update continuously.