Static Equilibrium, new to this subject, help please?

AI Thread Summary
The discussion revolves around solving a static equilibrium problem involving a beam supported by a hinge and a cable. The user is attempting to calculate the horizontal force exerted by the hinge on a beam inclined at 10.4 degrees, using basic trigonometric functions and torque equations. They express confusion about setting up the equations correctly, particularly in balancing forces and calculating torque. The user has tried breaking the problem into variables and has made some progress but received incorrect results from their calculations. Clarification on the setup and calculations for static equilibrium is requested to resolve the issue.
jcfor3ver
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Homework Statement



So I have looked at several ladder example problems, (the most basic for statics), but was given a problem by my professor that has me a little stumped. This is day 2 of learning for me and I am caught up, here's the problem:

A 30.8 kg beam is attached to a wall with a hinge and its far end is supported by a cable. The angle between the beam and the cable is 90o. If the beam is inclined at an angle of = 10.4o with respect to horizontal, what is the horizontal component of the force exerted by the hinge on the beam? (Use the `to the right' as + for the horizontal direction.)

I uploaded a pic so everyone can see the situation.



Homework Equations



Well any basic trig knowledge, cos, sin, and tan.

Torque=Force*distance.




The Attempt at a Solution



L=length
Theta
Nc= normal force by the cable
mg= mass times gravity
Fby-forcy by beam in y
Fbx= force by beam in x

I tried breaking it into letter variables first and solving that way instead of plugging in numbers the whole time.

I know I should set my Net force in all directions to zero.

I Set the force by the cable on the wall equal to the force of the beam in the x direction.
Then for the y direction the force of the beam (Fby)= mg

Then for torque I did T=-1/2Lcostheta(mg)+NcLsintheta

But I am really confused on how to set all of this up. Please help? I resulted with Nc=m/2*cottheta
But The number I entered gave me a wrong answer for the computer. What am I doing wrong?
 

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jcfor3ver said:
Then for torque I did T=-1/2Lcostheta(mg)+NcLsintheta

The cable is perpendicular to the beam, so the torque of Nc is simply Nc*L.

ehild
 
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