Tension needed for 440Hz A string on violin

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Torrie
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Homework Statement



  1. The A string on a violin has a fundamental frequency of 440Hz. The length of the vibrating portion is 32.4cm and has a mass of 0.340g. Under what tension must the string be placed?

Homework Equations


V = Fλ
Vs = √t/μ

The Attempt at a Solution


I plugged in my info to determine V = 142.604
then I attempted the second equation as:
T = .340(142.604^2)
This gave me the wrong answer
I also tried:
T = 1.049(142.604^2) - (.340g/.324m = 1.049g/m)
This also gave me the wrong answer. I am not sure what to do
 

Discussion

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Now I realize that v = 285.12. I forgot to multiple length by 2 to get the wavelength.
But I still can't figure out the second equation
 
Torrie said:
Now I realize that v = 285.12. I forgot to multiple length by 2 to get the wavelength.
But I still can't figure out the second equation
Make sure that your units all match (pay attention to your units for μ).
 
Should μ be kg/m?
So... 0.00034/.324m = .001049kg/m?
 
Torrie said:
Should μ be kg/m?
So... 0.00034/.324m = .001049kg/m?
Yes.
 
Okay so then I have

.001049(285.12^2) = 85.277

So the tension would need to be 85.277N?
 
Looks right to me. Be sure to round to the required number of significant figures.