In the figure, a uniform ladder 12 meters long rests against a vertical friction
ID: 2262482 • Letter: I
Question
In the figure, a uniform ladder 12 meters long rests against a vertical frictionless wall. The ladder weighs 400 N and makes an angle ?, of 78
In the figure, a uniform ladder 12 meters long rests against a vertical frictionless wall. The ladder weighs 400 N and makes an angle ?, of 78 degree with the floor. A man weighing 581 N climbs slowly up the ladder When he has climbed to a point that is 7.8 m from the base of the ladder, the ladder starts to slip. What is the coefficient of static friction between the floor and the ladder?Explanation / Answer
when man is at 7.8 m from base ,
balancing moment about floor point,
400cos78 x 12/2 + 581cos78 x7.8 = Nwsin78 x 12
Nw = 122.78 N
balancing forces in horizontal ,
f = Nw = 122.78 N
in vertical,
Nf = 400 + 581 = 981 N
f = us. Nf
122.78 = us. x 981
us =0.125