Hanging Sign Equations: Finding Tension and Force Exerted by Beam

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The discussion focuses on solving equations for tension and force exerted by a beam in a hanging sign scenario. The user initially calculated the tension (Ft) as 899.6 and the force exerted by the beam (F) as 422.7. However, it was pointed out that the calculated force could not be less than the vertical component of tension (Fty), indicating an error. Upon reevaluating the calculations with the correct value for Ft, the user found the correct tension to be 736.9. This highlights the importance of double-checking values in physics problems.
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upload_2015-11-18_3-27-35.png


Equations I used:
Fty = Ft(sinθ)
Ftx = Ft(cosθ)

My attempt:

I drew a free body diagram that looked like this (the red are just components of the tension, I know they wouldn't usually be included on a free body).
upload_2015-11-18_3-33-20.png


Finding Magnitude of Tension:
Fg = 516 (I gathered from the problem)
Fg = Fty
Fty = 516
Fty = Ft(sinθ)
516 = Ft (sin35)
Ft = 899.6

Finding Magnitude of Force Exerted By Beam:
Ftx = F
Ftx = Ft(cosθ)
F = Ft(cosθ)
F = 516 (cos35)
F = 422.7

I don't know where I went wrong, but I could really use some help figuring it out! Thanks!
 
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Olivia Carey said:
View attachment 92005
Finding Magnitude of Force Exerted By Beam:
Ftx = F
Ftx = Ft(cosθ)
F = Ft(cosθ)
F = 516 (cos35)
F = 422.7

Are you aware that you can see, that your answer can't be correct as F < Fty? By just comparing the lengths of the vectors it is obvious, that there must be a mistake.

Regarding the mistake: Your formulas are correct, you just plugged in a wrong value for Ft.
 
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stockzahn said:
Are you aware that you can see, that your answer can't be correct as F < Fty? By just comparing the lengths of the vectors it is obvious, that there must be a mistake.

Regarding the mistake: Your formulas are correct, you just plugged in a wrong value for Ft.

Thank you so much! I have no idea how I didn't catch that, but I guess that's why having a fresh pair of eyes always helps! I plugged in the correct value for Ft and got 736.9, which was correct.
 
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