A block is kept on a rough incline whose angle of inclination is greater than angle of repose then minimum force F required which is applied normal to the incline that will keep it in equilibrium

Options

A. `mg(sin theta - mu cos theta ) `
B. `mg(sin theta + mu cos theta ) `
C. `(mg)/(mu) (sin theta - mu cos theta )`
D. `mg""((sin theta - mu cos theta ))/(( cos theta + mu sin theta ))`

Answer

C

Explanation

`f_(L) = mg sin theta `
`mu N = mg sin theta `
`mu (F+mg cos theta )=mg sin theta `
`F=(mg )/(mu)(sin theta - mu cos theta)`