This demonstration illustrates the importance of statics and stability. Four chairs are positioned in a square, with the back of each chair facing outwards. Four volunteers are asked to sit on the chairs and lean backwards, so they are lying on the thighs of the person behind them. The chairs can then be pulled away and the “construction” remains stable
How does it work?
The four volunteers form a stable self-carrying construction. It only remains stable if all “elements” remain in their place. Other examples for self-carrying constructions are the Leonardo bridge and basements vaults.
