`mu` is coefficient of friction between all surfaces . Block A is kept over block B on inclined plane . The minimum force required such that 'A' block can accelerate along applied force is mg sin `theta + n mu g "cos" theta ` , calculate n .

Answer

5

Explanation

Frictional force developed in all surface is limiting
`F + 3 mg sin theta + 3 mu mg cos theta = 2T " " …… (i)`
`T - 2mg sin theta - 3 mu mg cos theta - mu mg cos theta = 0 `
`T = 2mg sin theta + 4 mu mg cos theta " " …… (ii)`
Solving the equation
F = `mg sin theta + 5 mu mg cos theta`