Engineering & MachinesGeometry
Why Three Legs Never Wobble
Three points always fit a surface; four often don't
The café table rocks, so you fold a napkin under one leg. A photographer's tripod never needs one. What does the tripod know?
You'll find out
- What a fourth leg ruins
- The turn that steadies a wobbly table
- Why chairs keep four legs anyway
Why it matters
Tripods, stools, robots and telescopes all lean on one fact of geometry. It also fixes the next wobbly table you meet.
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