Simultaneous Trig Equations for Tension in a Supported Bar

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The discussion revolves around solving simultaneous trigonometric equations for tension in a bar supported by two cables at different angles. The user initially struggles with the equations derived from the tension components, specifically T1sin(20) + T2sin(30) = 0 and T1cos(20) + T2cos(30) = 9800. Another participant suggests expressing T1 in terms of T2 and substituting it into the second equation to find T2, followed by T1. The user realizes the solution is straightforward once the correct substitution is made. The exchange highlights the importance of recognizing linear systems in physics problems.
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Homework Statement


I was working on a tension problem where a bar is supported by 2 cables at different angles.
I found the x and y vector components, but then got stuck at the simultaneous equations part.


Homework Equations


These are the equations i ended up with.

-T1sin(20) + T2sin(30) = 0
T1cos(20) + T2cos(30) = 9800

Not sure what to do, please help.
 
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Well it just seems like solving a simple linear system:

T1 = T2*sin(30)/sin(20)

Then just substitute that into the second equation and solve for T2. Then solve for T1.
 
haha. Yep, thanks, i saw how simple it was too late :P
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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