Question

please solve the problem question no 20 b..

Answer 1

☺️b-a sharp knife is more effective in cutting a apple than a blunt knife because the area of contact in the case of sharp knife is lesser than a blunt knife.
c- free fall is an any motion of a body where Gravity is the only force acting upon it .
I don't a answer pls don't worry someone else can give you answer

Answer 2

It is easier to cut an apple with a sharp edge of knife, because in the knife with sharp edge, The area contact between the sharp edge and knife is smaller and we know that the smaller the area of contact, the more is the pressure exerted by the sharp edge of knife and that is why, due to the sharp edge.

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