# Rigid body equilibrium

#### jesuslovesu

1. Homework Statement

http://img66.imageshack.us/img66/9317/inlinelt8.th.jpg [Broken]

3. The Attempt at a Solution
Sorry, By and B should be in lbs, not lbft
http://img141.imageshack.us/img141/9320/pictarsp4.th.jpg [Broken]

My work just shows how I attempted to find the force B. According to my book, the force B should be 2140 lb.

I'm really not sure if I handled the incline (force B) correctly. I know it's supposed to be perpendicular to the point of contact.

Does anyone see where I went wrong? As far as I can tell, the width of the beam (1.2ft) isn't important for finding any of the vector components.

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#### Doc Al

Mentor
Looks like you neglected the torque due to the horizontal component of force B. (That's where the beam width will come in.)

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