Find Weight in Homework Statement with Diagram

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The discussion revolves around a physics homework problem involving tension and compression in a diagram. The user calculates various forces but realizes a miscalculation in determining TBC, which affects subsequent calculations. A peer points out the error in the formula used for TBC and reassures the user that their overall approach is mostly correct. The user expresses concern about the impact of this mistake on their upcoming test. The conversation concludes with encouragement and a suggestion that the professor may consider the user's understanding despite the error.
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Homework Statement



http://img150.imageshack.us/img150/1196/cci0710200700003dy8.jpg
The problem and diagram is given on the sheet.


Homework Equations



sigma Fx=0
sigma Fy=0

The Attempt at a Solution



Starting freebody from point B
T=tension, C=compression

TBC = cos36.86deg = 3250N cos22.62deg
TBC = 81.39N

CBE = 81.39sin36.86deg + 3250sin22.62deg
CBE = 1.3KN

Now using Freebody at point C

TDCcos45deg = 81.39cos36.86deg
TDC=92.09N

M=92.09sin45deg + 81.39sin36.86deg
M=113.94N [FINAL ANSWER]

am i doing this correctly? did i make a mistake anywhere? I have a test tomorrow i need to know if i am missing some fundamental knowledge.

thank you for taking the time to help me.
 
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"TBC = cos36.86deg = 3250N cos22.62deg
TBC = 81.39N"

what happened here? TBCcos(36.86) = 3250cos(22.62) doesn't give TBC =81.39.

other than this your work looks right to me.
 
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shoot! yes you are correct. I don't know how I miscalculated. It is a risk using shift-ANS function on my calculator, sharp el520. if you press = it will overwrite the memory for ANS and you can't go back.

thank you. mistakes like this will ruin me on the test...if TBC is wrong then TDC will be wrong and so on.

thanks again learningphysics!
 
pooface said:
shoot! yes you are correct. I don't know how I miscalculated. It is a risk using shift-ANS function on my calculator, sharp el520. if you press = it will overwrite the memory for ANS and you can't go back.

thank you. mistakes like this will ruin me on the test...if TBC is wrong then TDC will be wrong and so on.

thanks again learningphysics!

Yeah, hopefully the professor will check your work and see what you were doing and only grade you down for that 1 mistake... this is the only mistake I saw in your work... I'd personally give you at least a 9/10... you're welcome. glad to help.
 
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