Muscles & Levers

Big forces for fast hands

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Limbs are levers: torques about the joint must balance.
• Muscles attach close to joints, pulling with many times the load.
• The trade-off buys speed and range of motion.

Steps

1. The forearm lever
2. Holding a ball
3. A bad design?
4. Moving the attachment
5. Standing on tiptoe
6. Lifting with your back