A cube of mass m is placed on top of a wedge of mass 2m, as shown in figure. There is no friction between the cube and the wedge. The minimum co - efficient of friction between the wedge and the horizontal surface, so that the wedge does not move is

Options

A. 0.1
B. 0.2
C. 0.3
D. 0.4

Answer

B

Explanation

(b)`a=g sin theta=(g)/(sqrt(2))`

`a_(H)=a_(V)=(g)/(sqrt(2))xx(1)/(sqrt(2))=(g)/(2)`
`(N)/(sqrt(2))=(mg)/(2)`…….(i)
`mg-(N)/(sqrt(2))=(mg)/(2)`……(ii)
`N'=(N)/(sqrt(2))+2 mg`……(iii)
`muN'=(N)/(sqrt(2))`…….(iv)

Solving above four equations, we get
`mu=0.2`