Imagine squashing a block the butter with the palm of her hand. The butter has to move out of the way, so it is squeezed sideways together it gets flattened. Currently use the leaf of her hand, prefer a slow-motion karate chop. The edge has much less surface area, so the pressure is greater and it is easier to press your hand through. Also, since the sheet is narrower, friend don’t must push so much of the butter out of the way. Rather of flattening the entirety block, you leaving a small slot.

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The tongue of a knife is like a really thin hand. It applies vast pressure in ~ the edge to push the product apart. When you try to reduced a tomato, a dull knife crushes a vast band of plant cells underneath it however a sharp knife will reduced through a single line of cells, separating the long-chain cellulose molecules in the cell wall.


The sharpest knives are those with the thinnest edges. Obsidian (a kind of glass) can be sharpened to an edge simply three atoms across. Obsidian scalpels are periodically used in surgery and also have been uncovered to produce less scarring, yet a narrow edge is more delicate and the obsidian blades become blunt an ext quickly than surgical steel.

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louis trained as a zoologist, yet now functions as a scientific research and modern technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared as soon as the revolution inevitably comes.


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