Ladder Leaning against wall -- find the coefficient of friction

[Pedgepoke]

Homework Statement

Ladder leans against wall at angle θ. It is L meters long and mass m. Find the coefficient of friction with the floor. Assume no friction at the top.[/B]

Homework Equations

ΣFx = 0
ΣFy = 0
Στ = 0
ƒ = μFn (Fn being the normal force with the ground)

The Attempt at a Solution

1. Drew free body diagram
2. Broke vectors into their respective sin and cos parts
3. Ended up with 4 complicated equations, 4 unknowns
4. Super complicated answer with a lot of sin, cos that are not solvable. Am I doing this right??

help

 

[haruspex]

Ladder leans against wall at angle θ. It is L meters long and mass m. Find the coefficient of friction with the floor. Assume no friction

Not enough information. I presume it also says the ladder is on the point of slipping, or maybe it actually asks for a lower bound on the coefficient.

Am I doing this right??

Doesn't sound like it, but not possible to help further without seeing your work.
Please post as typed in algebra, not an image.

 

[Dr Dr news]

As haruspex noted, you need to be more specific in your problem statement. Is this ladder on the verge of slipping? Are you looking for a range of angles where the ladder will not slip? How about when someone tries to climb the ladder? There may be a maximum height they can climb before slippage.

 

[CWatters]

Show your working. You might have missed some issues implied in the problem statement. For example zero friction at the wall means the reaction force there must be horizontal.

 

[Dr Dr news]

I would think you would end up with 3 equations since this is a static equilibrium problem in the x-y plane. ΣF(x) = 0, ΣF(y) = 0, Στ(z) = 0, τ = r x F,

 

[haruspex]

I would think you would end up with 3 equations since this is a static equilibrium problem in the x-y plane. ΣF(x) = 0, ΣF(y) = 0, Στ(z) = 0, τ = r x F,

Judging from post #1, it may be that F_f=μN is being counted as a separate equation.