Block A of mass m rests on the plank B of mass 3m which is free to slide on a frictionless horizo-ntal 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