- #1
Whotto
- 16
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Homework Statement
A mass suspended by a string is held 24o from vertical by a force of 13.8N as shown. Find the mass.
[PLAIN]http://img525.imageshack.us/img525/3421/problem32.jpg
2. The attempt at a solution
[PLAIN]http://img205.imageshack.us/img205/6100/attemptv.jpg
I've split it up the two given forces (F, and FT) by their axis and got the two equations:
1. [tex]13.8N Sin\ominus + F_{T}Cos24 = mg[/tex]2. [tex]13.8N Cos\ominus = F_{T}Sin24[/tex]
Continuing on to solving for FT with equation two, I get
3. [tex]F_{T} = \frac{Sin24}{13.8N Cos\ominus}[/tex]
I plug equation 3 into 1 to get
[tex]13.8N Sin\ominus + \frac{Sin24}{13.8N Cos\ominus}Cos24 = mg[/tex]
and solving for m to get:
[tex]\frac{13.8N Sin\ominus 13.8N Cos\ominus + Sin24Cos24}{9.8m/s^{2}} = m[/tex]
3. Where I'm stuck
I can't get theta to solve for m. I have tried to get it through geometry and any other ways I could think of. Am I missing information in order to solve this problem, or am I just not doing this correctly?
Any help would be appreciated. Many thanks!
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