For the arrangement as shown in the figure the maximum force F, for no relative motion between blocks is

Options

A. `12 N`
B. `8 N`
C. `20 N`
D. `24 N`

Answer

D

Explanation

To start motion `F gt 8 M`

Acceleration `=(F-8)/(8)`

`(F)/(2)-f_(r )= 3((F-8)/(8)) rArr (F)/(8)+3 = f_(r )`
`(F_(max))/(8)+3 =f_(Lm) = 6N rArr F_(max) = 24Nx`