Pulling force making an angle `theta` to the horizontal is applied on a block of weight `W` placed on a horizontal table. If the angle of friction is `alpha`, then the magnitude of force is `alpha` , then the magnitude of force required to move the body is equal to

Options

A. `(W"Cos"phi)/("Cos"(theta-phi))`
B. `(W"sin"phi)/("Cos"(theta-phi))`
C. `(W"Tan"phi)/("Sin"(theta-phi))`
D. `(W"Sin"phi)/("Tan"(theta-phi))`

Answer

B

Explanation

`N +P sin theta = mg, f = mu_(k) N` .