Description: A hands-on model shows how bones, joints, and muscles act as first-, second-, and third-class levers.
Objective
Identify lever classes in the body and measure mechanical advantage.
Materials
- Wooden base, dowels, small hinges
- Elastic bands (muscle), pins (fulcrum), weights
- Ruler, spring scale
Procedure
1. Assemble simple lever rigs (I, II, III class).
2. Map each to body examples (neck, calf, biceps).
3. Measure input vs. output force and distances.
4. Compute mechanical advantage (MA = load/effort).
Discussion
Trade-offs between force and speed/range of motion.
Conclusion
Human movement uses different lever classes to balance strength and mobility.
