Solving Hanging Sign Problem: Find Tension, Horizontal & Vertical Force

  • Thread starter Thread starter strugglin-physics
  • Start date Start date
  • Tags Tags
    Sign
AI Thread Summary
The discussion centers on calculating the tension in a guy wire supporting a shop sign and the forces exerted by the hinge on a beam. A sign weighing 206 N is supported by a 132 N beam, with the guy wire connected at a distance of 1.19 m from the backboard and at an angle of 43 degrees. The initial calculations presented for tension and forces are deemed incorrect due to mismatched units and improper torque considerations. Participants emphasize the importance of correctly identifying the forces and their points of action to solve the problem accurately. The conversation highlights the need for clarity in applying physics principles to avoid confusion in calculations.
strugglin-physics
Messages
47
Reaction score
0
A shop sign weighing 206 N is supported by a uniform 132 N beam of length L = 1.89 m as shown in figure below.

The guy wire is connected D = 1.19 m from the backboard. Find the tension in the guy wire. Assume theta = 43.0 o
Find the horizontal force exerted by the hinge on the beam.
Find the vertical force exerted by the hinge on the beam. Use "up" as the positive direction.

I get T = -mg * 1/2L + T*L*sin(43) = T = mg/2sin(40)

Fx = Hx -T cos(43) = 0
Hx = T cos(43)
Fy = Hy -mg + Tsin(43) = 0
Hy = mg - Tsin(43)

But these are incorrect. Where did I go wrong?
 

Attachments

  • gian0959.gif
    gian0959.gif
    5.5 KB · Views: 760
Physics news on Phys.org
"I get T = -mg * 1/2L + T*L*sin(43) = T = mg/2sin(40)"

This is complete nonsense!

You have 3 forces creating torques about the hinge. Which, and where do they act?
 
That wasn't suppose to be torque but rather tension.
 
It's still nonsense, since your units don't match (T and TL have not the same units)
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'A bead-mass oscillatory system problem'
I can't figure out how to find the velocity of the particle at 37 degrees. Basically the bead moves with velocity towards right let's call it v1. The particle moves with some velocity v2. In frame of the bead, the particle is performing circular motion. So v of particle wrt bead would be perpendicular to the string. But how would I find the velocity of particle in ground frame? I tried using vectors to figure it out and the angle is coming out to be extremely long. One equation is by work...
Back
Top