1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Introductory acoustics & noise control tutorial

  1. Nov 8, 2009 #1
    1. The problem statement, all variables and given/known data

    A small reverberation chamber is constructed with concrete walls. Its internal dimensions are 2 x 2.5 x 3m.
    Calculate the final steady-state sound pressure level produced by a source of 7.5microwatts acoustic output. Assume the absorption coefficient of the concrete to be 0.02.

    3. The attempt at a solution

    Well from a previous lecture on direct and reverberant sound we learnt that when time goes to infinity <p^2> = 4W*rho*c / a

    Using this I got <p^2> to equal 0.6225.

    (rho*c=415)
    (Pref=20x10^-6)

    Plugging this into Lp=10log10(0.6225/<Pref^2>) = 91.9dB

    However the answer is 76.2dB!

    Any help would be much appreciated,
    Thanks,
    Ben
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?



Similar Discussions: Introductory acoustics & noise control tutorial
  1. Fluid control (Replies: 0)

Loading...