Question

why do tools meant for cutting always have Sharp edges

Answer 1

Cutting need sharp tools so that they exert large pressure as the area it contacted is small.This is the reason why knives have sharp edges.


pressure and area are inversely proportional to each other.The more area,less will be the pressure and the smaller the area, large will be the pressure. 


Hope this helps..........................

Answer 2

The cutting edges of tools like blades, knives etc., are provided with sharp edges to cut the things easily as the sharp edges has small area on which the force is applied, hence more pressure is applied.