Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Sound Energy

  1. Dec 10, 2007 #1
    1. The problem statement, all variables and given/known data

    The sound level 24 m from a loudspeaker is 66 dB. What is the rate at which sound energy is produced by the loudspeaker, assuming it to be an isotropic source?


    2. Relevant equations


    Something to do with Intensity?

    3. The attempt at a solution

    I dont know where to begin on this problem. My book doesnt describe any problems that are related to distance nor does it have any equations that are related to distance.
  2. jcsd
  3. Dec 10, 2007 #2


    User Avatar
    Homework Helper

    This tests your understanding of "sound intensity", nature of sound propagation, and a bit of math.

    What is sound intensity? What are its units? (hint: W/area).

    At 24 meters, what is the surface area if sound radiates isotropically (i.e. like an expanding sphere).

    You'll have to convert from the dB to linear scale to get power in Watts.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook