Block A of mass m rests on the plank B of mass 3m which is free to slide on a frictionless horizontal surface. The coefficient of friction between the block and plank is 0.2. If a horizontal force of magnitude 2 mg is applied to the plank B, the acceleration of A relative to the plank and relative to the ground respectively, are :

Options

A. `0,(g)/(2)`
B. `0,(2g)/(3)`
C. `(3g)/(5),(g)/(5)`
D. `(2g)/(5),(g)/(5)`

Answer

D