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Intensity and Wattage

by tadisc
Tags: intensity, wattage
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Dec1-11, 12:34 AM
P: 3
1. The problem statement, all variables and given/known data
OK, so this is a very basic question but i am uncertain what the relationship is. I know its logarithmic, but i don't know how to draw a conclusion. Here is the question:
If you want an amplifier which will give a sound output which is twice as lod as your present 20 W amplifier, what amplifier power should you buy? What if you wanted a sound output four times as loud?

2. Relevant equations

3. The attempt at a solution
I know that the relationship between Intensity and Wattage is logarithmic, but how do i draw a numeric conclusion?
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Simon Bridge
Dec1-11, 05:40 AM
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Are they looking for loudness or intensity?

The wattage of the amplifier is the maximum power it can supply to the signal.
The intensity a wave is the square of it's amplitude.
I suspect you are thinking of decibels.

If you double the amplitude, you get four times the intensity.

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