Physics
Explain why scissors for cutting cloth may have blades longer than the handles, but shears for cutting metals have short blades and long handles.
Answer
A pair of scissors which is used to cut a piece of cloth has blades longer than the handles i.e. it has effort arm shorter than load arm so that the blades move longer on the cloth when the handles are moved a little.
Shears used for cutting metals have short blades and long handles i.e. it's effort arm is longer than the load arm and acts as a force multiplier which helps us to overcome large resistive force by a small effort.
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