Tension in string - hanging block

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The discussion centers on calculating the tension in string 1 of a hanging block system. The original poster finds a tension of 23 N, while the solution manual states it should be 34 N. The calculations involve using the y-component of string 2's tension to equal the block's weight and the x-component to relate to string 1's tension. After clarification, it is confirmed that the correct tension in string 1 is indeed 23 N, contradicting the manual. The conversation emphasizes the importance of clearly writing out equations step by step for accuracy.
tony873004
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Homework Statement


Find the tension in string 1
hangingmass.GIF

I don't get the same answer as the solution manual.

My attempt:
The y-component of string 2’s tension must equal the weight of the block.
The x-component of string 2’s tension must equal the tension of string 1.
T1=T2x=T2y/tanθ =23°

solution manual says 34 N.

 
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tony873004 said:
My attempt:
The y-component of string 2’s tension must equal the weight of the block.
The x-component of string 2’s tension must equal the tension of string 1.
Good.
T1=T2x=T2y/tanθ =23°
Not sure what you did here (better to write the equations step by step), but I think you found that the tension in string 1 is about 23 N (not degrees!). Sounds right to me.

solution manual says 34 N.
I'd say that was wrong.
 
Doc Al said:
...Not sure what you did here (better to write the equations step by step).

tanθ=opposite/adjacent
tanθ=T2y/T2x
tanθ=mg/T2x
T2x=T1=mg/tanθ = 23 N (oops,not degrees!)

Thanks Doc Al! Just wanted to make sure I wasn't crazy!
 
tony873004 said:
tanθ=opposite/adjacent
tanθ=T2y/T2x
tanθ=mg/T2x
T2x=T1=mg/tanθ = 23 N (oops,not degrees!)
Much better.

Thanks Doc Al! Just wanted to make sure I wasn't crazy!
You are welcome.
 
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