Question

Give reason sharp knife is more effective in cutting of fruits

Answer 1

Because sharp edge will shear the surface of the object better than a blunt edge. The sharp edge has smaller surface area and imparts greater pressure for the same applied force. It’s practical in life as well. Try it at your home, take a sharp knife from the kitchen and try to cut some vegetable with it and observe the pressure that you applied. Now take a blunt knife and repeat the same. You'd observe that the sharp knife required lesser force to cut the object and the cut was clean while the cut with the blunt knife would be rough and would require more pressure to cut

Answer 2

area decrease pressure increases so it is more effective in cutting of fruits
and pressure is directly proportional to 1/area