Eli5: why are the tips of scissors worse at cutting than the base?
In: 38
The amount of energy dissipated by the scissors is directly proportional to the length of the line cut through the material. Meaning the power (Joules per second) is proportional to the speed of the intersection point between the blades as the angle between the scissors is changed.
Using the angular separation of the blades as an independent variable, the power is proportional to its cotangent. This is a value that is close to 0 when the blades are at a right angle and hardly cutting anything, and approaches infinity when the blades approach being parallel and the intersection point travels infinitely fast. So when the angle is close to zero and the intersection point is near the tip, you have to squeeze harder to keep the angle changing at a constant rate.
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