The Arch is an ancient piece of technology and still common now days. Here is showing how you can make your own arch with potato or other hard vegetables.
Building of an arch is simple, you have to make blocks of potato that are slightly wider at the top than the bottom.
So cut a few large chips out of the potato which are about 12-15 millimeter square and as straight as possible.
Although the blocks you make are tapered in one direction all the other corners should be right angles or your arch will be wonky, so using a set square, or something similar with a good right angle is useful to make the blocks the right shape.
When you have made sufficient blocks to make a half circle try putting them together to make an arch
How does an arch work?
The arch is made up of blocks, and will stand with nothing attaching them together. The central block stays up because it is wider at the top than the bottom, so to fall down it would have to push the neighboring blocks outwards, as long as these are held securely the central block can't fall down.
Experiment Resource: thenakedscientists.com
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