A wedge of mass 2m and a cube of mass m are shown in figure. Between cube and wedge, there is no friction. The minimum coefficient of friction between wedge and ground so that 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`