at top
force to left from wall = Fxt
vertical force from wall = 0
at bottom
Force up from floor = Fzb
max force to right from floor =Fxb
= .4 Fzb
Gravity force down at 10 meters from base = 750 N
not accelerating so
Fzb = 750
Fxb = .4(750)
so
Fxt also = .4(750) but to left
angle to floor = T
take moments about center of ladder
Fzb (10 cos T) = Fxb (10 sin t) + Fxt(10 sin T)
750 cos T = 2 (.4*750) sin T
tan T = 1/.8
A uniform ladder of length 20.0m and weight 750 N is propped up against a smooth vertical wall with its lower end on a rough horizontal surface. The coefficient of friction between the ladder and this horizontal surface is 0.40.
(b) Work out and add the numerical values of each force clearly showing your justification in each case.
(c) Hence, calculate a value for the angle between the ladder and the wall if the ladder just remains in stable equilibrium
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