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Homework Help: Sound Intensity of a workplace

  1. Mar 29, 2010 #1
    Accoding to US government regulations, the maximum sound intensity levels in the workplace is 90,0 dB. Within one factory, 32 ihdentical machines produce a sound intensity level of 92,0 dB. How many machines must be removed to bring the factory into compliance with the regulation?

    Possible answers:
    a) 2
    b) 8
    c) 16
    d) 24
     
  2. jcsd
  3. Mar 29, 2010 #2

    Integral

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    You need to show us some of your thoughts and effort put into this proplem.
     
  4. Mar 31, 2010 #3
    My attempt:

    β_1=90.0 dB,β_2=92.0 dB
    B2-B1= 10log(I1/I0)-10log(I2/I0)
    =10log(I2/I0/I1/I0)
    =10log(I2/I1)
    0.2 =log(I2/I1)
    Therefore: I2/I1=10^(0.2)= 1.58
    32 machines/1.58 ≈20
    The number of machines that must be removed is 32-20=12
    Is that right?
     
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