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Homework Help: How to find energy of sound wave

  1. Jan 3, 2012 #1
    1. The problem statement, all variables and given/known data
    In room temperature air, which of the following sound waves would have the greatest energy associated with it?

    A. A wave with lambda equal to 4.7 on
    B. A wave with a frequency of 2.6 Hz
    C. A wave which has a distance between adjacent nodes (1/2lambda) of 21mm

    2. Relevant equations
    v = f x lambda ?
    maybe KE = 1/2mv^2 and PE = PGH?
    no idea.

    3. The attempt at a solution
    I'm not exactly sure what an "on" is (referring to letter A, unless that's supposed to be inches? not sure).

    A =
    B = 2.6 Hz
    already stated
    C = 1633Hz, so above B.
    343 = f x .021
    343/.21 = 1633Hz
    I know higher frequency = higher energy.. so I know The answer is either A or C. Since I don't know what an "on" is, I'm having trouble solving for it. Thanks.
  2. jcsd
  3. Jan 3, 2012 #2
    I'm so confused :*(
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