A uniform ladder 5.0 m long rests against a frictionless, vertical wall with its lower end 3.0 m from the wall. The ladder weighs 180 N. The coefficient of static friction between the foot of the ladder and the ground is 0.40. A man weighing 800 N climbs slowly up the ladder.
(a) What is the maximum frictional force that the ground can exert on the ladder at its lower end?
? N
(b) What is the actual frictional force when the man has climbed 1.0 m along the ladder?
? N
(c) How far along the ladder can the man climb before the ladder starts to slip?
? M