Solving Static Equilibrium: 15.5 m Ladder & 500 N Weight

[xdevinx]

Homework Statement

A 15.5 m uniform ladder weighing 500 N rests against a frictionless wall. The ladder makes a 56.0° angle with the horizontal.

(a) Find the horizontal and vertical forces the ground exerts on the base of the ladder when an 810 N firefighter is 4.10 m from the bottom.

Magnitude of the horizontal forceMagnitude of the vertical force(b) If the ladder is just on the verge of slipping when the firefighter is 9.20 m up, what is the coefficient of static friction between ladder and ground?

Homework Equations

I have no idea how to do this /:
All I know is that the sum of the forces in the x and y direction has to equal 0.
Other than that...

The Attempt at a Solution

 

[Doc Al]

All I know is that the sum of the forces in the x and y direction has to equal 0.

Good--that describes translational equilibrium. What's the condition for rotational equilibrium?