A question about string tension

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    String Tension
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The discussion centers on calculating the tension required for a violin A string with a fundamental frequency of 440Hz, a vibrating length of 31.2cm, and a mass of 0.355g. The participant is attempting to derive the string's velocity using the relationship between tension, mass, and length, while also considering the conversion of mass from grams to kilograms for accurate calculations. They propose using the formula that relates velocity to frequency and wavelength to find the velocity, which they calculate as 282.48 m/s. The importance of unit consistency is emphasized, particularly the need to convert mass to kilograms to express tension in Newtons. The discussion highlights the critical steps in applying physics equations to solve for string tension.
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Homework Statement



The A string on a violin has a fundamental frequency of 440Hz.
The length of the vibrating portion is 31.2cm and has a mass of
0.355g. Under what tension must the string be placed? (Find the
answer in the usual metric unit of tension, the Newton, but do not enter
units)


Homework Equations



square root of Tension/(mass/length) = velocity of string.

Velocity = frequency X wavelength

The Attempt at a Solution



Soo... V = square root OF Tension/ (.355g/.321 m) (or do I need to convert grams to kilograms?)

So to find velocity i was thinking V = frequency X wavelength. So... (440Hz X .642) which is 282.48..

So velocity = 282.48? then that would mean that 282.48 = squareroot of Tension/ (.355g/.321 m) ?

Am I on the right track?
 
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Always keep an eye on units. Since you need tension in Newtons, you mass always needs to be in kilograms (1 Newton is equal to 1 kg.m.s-2)
 
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