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!

Sound Intensity and Threshold of hearing

  1. Jan 16, 2013 #1
    My textbook says that in the equation β= 10log(I1/I2), I1 in most cases is the threshold of hearing (1.0x10^-12). Just out of curiosity, when is I1 not the threshold of hearing?
     
  2. jcsd
  3. Jan 16, 2013 #2

    lightgrav

    User Avatar
    Homework Helper

    the reference intensity for zero dB, is 1 pico-Watt/m^2 . I can't hear such faint sounds anymore, especially at the edges of my frequency range. I used to be able to hear 1/8 picoWatt/m^2 ... that's -9 dB ... at 880 Hz.
     
  4. Jan 18, 2013 #3
    Well sound intensity is the measure of a ratio of two sound intensities, when we are discussing the sound intensity experienced by people, then it is useful to set this 'reference' level at the average threshold of human hearing. In any situation when you are not concerned with sound intensity as experienced by people, you might choose a different reference level, it would depend on what you wanted to measure.
     
  5. Jan 19, 2013 #4
    Oh okay, i see that makes more sense. I was always wondering why we placed that value as I1, there seemed to be no explanation from my book, it simply stated to do so
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Sound Intensity and Threshold of hearing
Loading...