Determine the largest weight of the lamp that can be supported

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The maximum weight of the lamp that can be supported is determined to be 24.4 lb, based on the tension limits of the cords. To find the angle θ of cord DC for equilibrium, further analysis is needed, as the tension values provided (T(1)=12.63 lb, T(2)=17.86 lb, T(3)=30.93 lb) depend on this angle. Without knowing θ, the accuracy of the weight calculation remains uncertain. The discussion emphasizes the importance of understanding the forces in a free body diagram (FBD) to solve for θ and ensure the system's stability. Accurate determination of the angle is crucial for confirming the maximum weight supported by the lamp.
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Homework Statement



Hibbeler14.ch3.p34.jpg

Each cord can sustain a maximum tension of 31 lb .

Determine the largest weight of the lamp that can be supported.
Determine θ of cord DC for equilibrium.

Homework Equations

The Attempt at a Solution


I found the answer to the first part of the problem (24.4lb) but not sure how to get theta.
 
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How did you get the maximal weight without knowing the angle?
Robb said:
but not sure how to get theta.
What did you try so far?
What is the first step?
 
Sorry for the hand written notes. The answer to the first part is boxed in in the middle of the page. I haven't really done anything other than stare at my equations for the second part. I assume I am working with the equations associated with the FBD at the bottom of the page. T(1)=12.63lb., T(2)=17.86lb, T(3)=30.93lb
upload_2016-10-2_20-47-40.png
 
As mfb posted, you cannot be sure of your answer to a) until you have found theta.
You can find T4 from analysis of B.
 
The CD connection could break as well. You cannot know when that happens without the angle.
 
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