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Paper Bridge

Construct a paper-bridge carrying a glass of water.


- one glass of water
- two empty glasses
- a piece of paper



Fold the paper follwing a zick zack pattern: One stripe (width) to the back, one stripe to the front ...

Turn the empty glasses up-side-down and place the folded paper on them. The paper's center should not lay on a glass' bottom.

Now place carefully the glass of water on the center of the bridge. What happens?


The glass of water is carried by your paper=bridge, but why. An unfolded paper is not able to carry a glass of water. The trick is the direction of bending paper. A piece of paper, which lays on the a desk, can be easily bend by taking one end end and place it on the opposite end. But without lifting the paper it is impossible to bend the paper and not ripping it. Our paper bridge is using this fact. The single striped of our zick-zack-pattern are almost vertical and therefore the thickness of the brigde increase a lot folding the paper. It is much harder to bend the folded paper. We can also place a glass of water on the bridge.