A triangular block of mass M with angle 30º, 60º, 90º rests with its 30º– 90º side on a horizontal smooth fixed table. A cubical block of mass m rests on the 60º – 30º sideofthe triangular block. What horizontal acceleration a must M have relative to the stationary table so that m remains stationary with respect to the triangular block [M = 9 kg, m = 1 kg]

Options

A. `g`
B. `(g)/( sqrt(2))`
C. `(g)/( sqrt(3))`
D. `(g)/( sqrt((3))`

Answer

C

Explanation

As, it is clear from the figure, the block of mass m remains stationary relative to the triangular block, when
`m a cos 30^@ = mgsin30^@`

` or a xx ( sqrt( 3))/(2) = (g)/(2 ) or a=(g)/( sqrt(3))`