Static Equilibrium, new to this subject, help please?

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SUMMARY

The discussion revolves around solving a static equilibrium problem involving a 30.8 kg beam attached to a wall with a hinge and supported by a cable at a 90-degree angle. The user is tasked with finding the horizontal component of the force exerted by the hinge on the beam, given that the beam is inclined at 10.4 degrees to the horizontal. Key equations mentioned include torque calculations and the need to set net forces in all directions to zero. The user expresses confusion over the setup of the problem and the calculations leading to incorrect results.

PREREQUISITES
  • Understanding of static equilibrium principles
  • Basic trigonometry (sine, cosine, tangent)
  • Knowledge of torque calculations
  • Familiarity with free body diagrams
NEXT STEPS
  • Review static equilibrium problems involving beams and cables
  • Study the application of torque in static systems
  • Practice drawing and analyzing free body diagrams for complex structures
  • Learn how to resolve forces into components in two-dimensional systems
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Students studying physics, particularly those focusing on mechanics and static equilibrium, as well as educators seeking to provide guidance on similar problems.

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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