An open knife of mass m is dropped from a height h on a wooden floor. If the blade penetrates up to the depth d into the wood. The average resistance offered by the wood to the knife edge is .

Options

A. `mg`
B. `mg(1-(h)/(d))`
C. `mg(1+(h)/(d))`
D. `mg(1+(h)/(d))^(2)`

Answer

C