What are the cord tension and force on the hinge for this angled beam?

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Homework Help Overview

The discussion revolves around determining the cord tension and the force on the hinge of an angled beam, with specific parameters including the beam's weight and length. Participants are analyzing the forces and torques acting on the system.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants explore the relationship between the angle of the beam and the forces acting on it, questioning the need for sine and cosine components in their calculations. There is discussion about the torque equations and the implications of the beam's angle on the forces involved.

Discussion Status

Some participants have provided insights into the torque calculations and the role of angles in determining the forces. There is an acknowledgment of the complexity of the problem, with multiple interpretations of the forces at play being explored. One participant claims to have resolved their confusion.

Contextual Notes

Participants are working under the constraints of a homework assignment, which may limit the information available and the methods they can employ. There is an ongoing examination of the assumptions related to the angles and the forces acting on the beam.

hangingwire
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Homework Statement


Find cord tension and force on the hinge on this beam given the following:

Picture of the equation (in attachments)
beam is 10 kg
beam is 8.0m long

Homework Equations



[T=0
[F=0

[h2]The Attempt at a Solution[/h2]

Finding the Torque on the wire...
I attached my FBD I drew. Before I start, one question? Since the beam is on an angle, would there be a horizontal force on the x-axis resulting from the Mass of the beam? If so, It could be 60 degrees? Mg Sin60?

That is my attempt using the "Z-rule" in angles

Anyways:

[T= 0
Tcw = Tccw
mg(d) = Tsin( ) * (d)
(10)(9.8)(4) = T sin30 * (8m) ----> Sin 30* given that directly across is 90 degrees + 60 degrees given = 30 degrees left at where the beam and wire are attached.

392N = T sin30 * (8m)

392N divided by 8m = 49

49 = T sin30

49 divided by sin30 --> 98?

The answer is 49N. Why did I get double the answer? Is there something with my angles?
 

Attachments

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The weight of the beam acts at angle to the "arm", so its torque must involve the sine of the angle. Intuitively that should be fairly clear: the "more vertical" the beam gets, the easier it is to hold it in place.
 
So instead of "Mg" just being "Mg". It is "Mgsin(30)"? Is that what you are trying to say? If I change that in my equation it works out?

If that is the case, waste no time to say... Would the horizontal axis on Mg also require a MgCos(30) to workout the force from the hinge in components?
 
It should be fairly obvious that 49 sin 30 = T sin 30 implies T = 49.

Regarding the forces, the answer is no. If you you use the horizontal and vertical axes, then the weight is purely vertical - it always is; the other forces, however, are not.
 
Figured it out! Thanks
 
Last edited:

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