How to Calculate Wave Velocity in a Tuned Violin String

AI Thread Summary
To calculate the wave velocity in a tuned violin string of 31.6 cm, the fundamental frequency (f_0) is determined to be 440 Hz, based on the observed frequencies of 880 Hz and 1320 Hz, which correspond to overtones. The wave velocity is calculated using the formula v = f * λ, where λ is twice the length of the string (0.316 m), resulting in a velocity of approximately 278.08 m/s. However, the answer key states the velocity as 275 m/s, leading to speculation about potential rounding discrepancies. Participants in the discussion agree that the difference is likely due to rounding rather than an error in the calculations. Overall, the calculations appear correct, with rounding being the only point of contention.
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Homework Statement


A tuned violin, with strings of 31.6 cm each, is placed in front of a speaker. When varying the speakers frequency between 500 and 1500 Hz, it was discovered that a certain string only vibrated at 880 Hz and 1320 Hz. Determine the velocity of the wave in this string.


Homework Equations


v=fλ


The Attempt at a Solution


The frequencies has to be overtones or the fundamental tone f_0. That gives nf_0=880 Hz and (n+1)f_0=1320 Hz, so n=2 and f_0=440 Hz. When f=f_0 the string has two nodes so v=f_0*2l (l=0.316m). v=278.08. But the key says 275 m/s, did I do something wrong or have they rounded it weirdly? Thanks
 
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I don't see anything wrong in your solution. It most probably is a case of rounding off weirdly.
 
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Adithyan said:
I don't see anything wrong in your solution. It most probably is a case of rounding off weirdly.
Yes, has to be so. Thanks :)
 
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