You're trying to open a heavy door. You push with the same force in two spots: once at the handle (far from the hinge), and once right next to the hinge.
Pushing near the hinge compared to the handle requires:
Torque = distance × force. Near the hinge (small r), you need enormously more force to get the same rotation!
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Click different points on the door to push. Watch how the torque and angular acceleration change.
τ = r × F
Double the distance → double the torque, with the same force
Longer wrenches make loosening bolts easier — more lever arm
Always placed at the far edge from hinges to maximize torque
A heavier child sits closer to the pivot to balance a lighter child
“Force makes things move. Torque makes things spin.”
Lever Lab
Balance objects on a beam by adjusting positions and masses. Discover the law of the lever.
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Place a 10 kg weight 1 meter from the pivot. How far must a 2 kg weight be to balance it? Does the answer surprise you?
The lever principle (m₁r₁ = m₂r₂) lets a small force balance a large one. This is behind every wrench, wheelbarrow, and seesaw.