A ladder of length `5 m` is placed against a smooth wall as shown in figure. The coefficient or friction is `mu` between ladder and ground. What is the minimum value of `mu` , If the ladder is not to slip?

Options

A. a. `mu = (1)/(2)`
B. b. `mu = (1)/(4)`
C. c. `mu = (3)/(8)`
D. d. `mu = (5)/(8)`

Answer

C

Explanation

`N_(1) = mu N_(2)`
`N_(2) = w`
`sum M_(B) = 0`
`w ((3)/(2)) = N_(1) (4)`

On solving these equation, we get
`mu = (3)/(8)`