Help with a physics sound problem.

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SUMMARY

The discussion focuses on calculating the beat frequency produced by two identical cello strings tuned to 440 Hz, where one string's tension is decreased by 1.5%. The initial calculation yielded a beat frequency of 6.6 Hz, but the correct answer is 3.3 Hz. The key formula for wave velocity on a tensioned string, v = √(F / µ), is crucial for understanding the relationship between tension, velocity, pitch, and wavelength, leading to the correct beat frequency calculation.

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  • Understanding of wave mechanics and sound frequency
  • Knowledge of tension in strings and its effect on pitch
  • Familiarity with the formula v = √(F / µ)
  • Basic concepts of beat frequency in acoustics
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  • Explore the implications of string density (µ) on wave velocity
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maninthesuit
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1. Two identical strings on different cellos are tuned to the 440-Hz A note. The peg holding one of the strings slips, so its tension is decreased by 1.5%. What is the beat frequency heard when the strings are played together?
f₁=440Hz; Tension decrease=1.5%2. f(beat)=|f₁-f₂|3.
f₂=440Hz - (440Hz*.015)=433.4Hz
f(beat)=|440Hz-433.4Hz|=6.6Hz

The answer is supposed to be 3.3Hz. I would really appreciate the help. Thanks.
 
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I think you're missing a key formula here.
Remember that the velocity of the wave on a tensioned string is

v = √(F / µ) where µ is the string density. Use it more conceptually now, and think about the relationship of the force to the velocity, and the velocity to the pitch and wavelength.
 
Thank you very much. I got the right answer now. Much appreciated. :)
 

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