Calculating Frequency Shift for Temperature Change in Musical Instruments

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To determine the finger placement on a guitar string to play A above middle C (440 Hz) from E (330 Hz), the speed of sound in the string was calculated to be 231 m/s, leading to a required distance of 0.525 m from the end of the string. For the second problem regarding frequency change with temperature, it was noted that the speed of sound varies with the square root of temperature, requiring temperature conversion to Kelvin for accurate calculations. The discussion emphasizes the importance of understanding the relationship between frequency, wavelength, and temperature effects on sound. Overall, the calculations and concepts presented provide a solid foundation for solving the problems related to frequency shifts in musical instruments.
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Homework Statement


1. An unfingered guitar string is 0.70 m long and is tuned to play E above middle C (330 Hz). How far from the end of this string must the finger be placed to play A above middle C (440 Hz)?

2. An organ is in tune at 20 degrees C. By what fraction will the frequency be off at 0 degrees C?

Homework Equations



The Attempt at a Solution



1. I used the v=(freq)(wavelength) equation:
v = (330)(0.70) = 231 m/s
Then i plugged in 231 to figure out the distance for 440 Hz:
(231 m/s) = (440)x
x=.525 m
I'm not sure if my method is right, so please check that! thanks

2. Not sure about this one

Thanks for the help
 
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I think that's right.

For the second part,
v=\sqrt{\frac{\gamma RT}{M}} The temperature should be in Kelvin. Since there is no change in the gas, \frac{\gamma R}{M} are constant, and so the speed of sound varies with the square root of temperature. That should help you out.
 
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