A block of mass m is placed on a rough horizontal surface. If minimum force to pull the block is `(mg)/(2)` then coefficient of friction is :

Options

A. `(1)/(2)`
B. `sqrt3`
C. `(1)/(sqrt3)`
D. None

Answer

C

Explanation

`F_("min") = (mu mg)/(sqrt(1 + mu^(2)))`
`(mg)/(2) = (mu mg)/(sqrt(1 + mu^(2)))`
`(1)/(4) = (u^(2))/((1 + mu^(2)))`
`(1)/(3) = mu^(2)`
`mu = (1)/(sqrt3)`