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Audible frequency in xenon gas, please help.

  1. Mar 14, 2009 #1
    You come to a landing on Congress. Actually, it was more a splash-down than a landing as Congress is made up of mostly ocean. Consulting your favorite book, you read that Congress has a radius of ro= 9·105 meters. Due to a large core of the element Administratium the average density of the planet ends up giving it a surface gravity of 25m/s2. The atmosphere is mostly Xenon with a density profile that looks like p(r)=3*p0*e^(r0-r) where ρ0 is the standard density of dry Earth air at Earth sea level

    You come to the dock of a small island and find yourself surrounded by reporters. The reporters of Congress however are only 20cm tall and look slightly like a Peruvian puma. You say “Dude!” None of the reporters seem to hear you. You give yourself a dopeslap as you remember that you’ll need to speak at a different pitch so that these puma-like reporters can hear you. You can’t remember of the top of your heads (you have two of them) at what frequency they speak, so you look at them, consider what the atmosphere is make out of, do some calculations and choose a frequency at which to say “Dude!”.

    6. What frequency do you choose and why did you choose it?

    2. Relevant equations
    frequency = velocity/wavelength

    3. The attempt at a solution
    average frequency of conversation is 500 Hz, and the velocity of sound in xenon is 169 m/s?? maybe. so I tried a ratio of velocity of sound on earth divided by velocity of sound in xenon equal to the 500 Hz divided by x Hz where x is the frequency observed on congress at normal conversation. which gave me 246.356, then I found a constant multiplier taking 500/246.356 = 2.03 so the frequency I would choose is 2.03*500 = 1014.79 Hz

    I can't find any other way to solve this, and I don't think a ratio will be acceptable.
    Any real suggestions are appreciated. Thank you
  2. jcsd
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