A Ladder of Uniform Density,length L and Weight W Rests $\circ$

Multiple Choice

A ladder of uniform density,length L and weight W rests on a rough floor (µ_s = 0.45) and against a frictionless wall.The maximum value of the angle between the wall and the ladder to prevent slipping is

A) 42 ^$\circ$ .
B) 37 ^$\circ$ .
C) 29 ^$\circ$ .
D) 24 ^$\circ$ .
E) 19 ^$\circ$ .