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## Homework Statement

you want to hang a 15-N picture as in part (a) using some very fine twine that will break with more than 12 N of tension can you do this? what if you have it as illustrated in part (b) of the figure?

## Homework Equations

Σf=ma

## The Attempt at a Solution

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okay i started with finding the tensions in part (a). using:

**Σfx= 0**and so

T2 cos30=T1 cos50

*T2=0.74 T1 ---------(1)*

**Σfy=0**

T1sin50 + T2sin30= W

*0.76T1+0.5T2 = 15-------(2)*

substituting (1) in (2)

0.76T1 +0.5 (0.74 T1)=15

0.76 T1 + 0.37 T1 =15

1.13 T1= 15

**T1= 13.27N**

and so

**T2= 9.82 N**

Now what i am not sure about, is first how to know if the ceiling is fine with these tensions or not? I mean should I only find the vertical forces of the tensions here (T1sin50 & T2 sin 30) and see if they are larger than 12 ( obviously they are ) or what?

and regarding the part B. I am also hesitated about using the same Tension values computed from the first part (a) in b also!

Now what i am not sure about, is first how to know if the ceiling is fine with these tensions or not? I mean should I only find the vertical forces of the tensions here (T1sin50 & T2 sin 30) and see if they are larger than 12 ( obviously they are ) or what?

and regarding the part B. I am also hesitated about using the same Tension values computed from the first part (a) in b also!

thanks in advance

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