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Calculating decible increases

  1. Feb 9, 2010 #1
    I was wondering how I would go about calculating decible levels with increasing fans. Here I'll explain
    1 fan is 45 decibles but we know that 2 fans is not 90 decibles, so I was wondering how i would go about calculating how many decibles 8 fans is.
  2. jcsd
  3. Feb 9, 2010 #2


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    Decibels are on a log scale. Ten decibels (one bel) means the energy of the sound is ten times as much. For 2 fans add 10log2 ~ 3. For 8 add 10log8. The log in this equation is to base 10.
    Last edited: Feb 9, 2010
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