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## Homework Statement

. The sign shown below consists of two uniform legs attached by a frictionless hinge. The coefficient of friction

between the ground and the legs is µ. Which of the following gives the maximum value of θ such that the sign will

not collapse?

(A) sin θ = 2µ

(B) sin θ/2 = µ/2

(C) tan θ/2 = µ

(D) tan θ = 2µ

(E) tan θ/2 = 2µ

Diagram here : http://www.aapt.org/physicsteam/2014/upload/exam1-2013-1-6-unlocked.pdf

Page 2, Diagram 6

## Homework Equations

## The Attempt at a Solution

I drew a FBD and got a force of gravity for each leg with force mg down (relative to the surface on the ground) , normal force of mgcos((180-theta)/2) up (relative to the surface of the leg), and friction of mu*N towards the interior of the sign. The question is where do I go from here?