# Torque Equilibrium problem

#### vipertongn

1. Homework Statement

A uniform ladder of length L and mass m1 rests against a frictionless wall. The ladder makes an angle θ with the horizontal.
(a) Find the horizontal and vertical forces the ground exerts on the base of the ladder when a firefighter of mass m2 is a distance x from the bottom. (Answer using m_1 for m1, m_2 for m2, theta for θ, g for gravity, and L and x as necessary.)
horizontal

(b) If the ladder is just on the verge of slipping when the firefighter is a distance d from the bottom, what is the coefficient of static friction between ladder and ground?

2. Homework Equations

Net Fy = 0
Net Fx = 0
Net T = 0

3. The Attempt at a Solution

I tried n_g-m_1*g-m_2*g as the answer for the vertical force because the ladder has a normal force that is exerted in reaction to the two gravitational forces from the ladder itself and the firefighter. I believe that this isn't the correct way to input it.

for the force for horizontal I know its the frictional force minus the normal force from the wall. however I don't know how to input it using hte variables they want.

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#### tiny-tim

Homework Helper
A uniform ladder of length L and mass m1 rests against a frictionless wall. The ladder makes an angle θ with the horizontal.
(a) Find the horizontal and vertical forces the ground exerts on the base of the ladder when a firefighter of mass m2 is a distance x from the bottom. (Answer using m_1 for m1, m_2 for m2, theta for θ, g for gravity, and L and x as necessary.)
horizontal

(b) If the ladder is just on the verge of slipping when the firefighter is a distance d from the bottom, what is the coefficient of static friction between ladder and ground?
Hi vipertongn!

Yes, the normal force will be equal and opposite to the other vertical forces.

To find the horizontal forces, take moments about some convenient point.

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