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View Full Version : Pre calculus intensity and inverses


jgiffor86
Mar 23, 2009, 12:30 PM
The noise level, N, of a sound in decibels is given by
N=f(I)= 10log(I/I0) <---the 0 in the (I/I0) is a sub 0

where I is the intensity of the sound and I0 (sub 0) is a constant.
Find and interpret f-1(N) the inverse

I don't know how to even go about doing this??

ebaines
Mar 23, 2009, 12:47 PM
You have an equation like this:


N = 10 \cdot log( \frac I {I_0})


so they want you to work this so that you get I all by itself. The only trick here is to use the fact that if

a = log_b c

then

b^a = c

jgiffor86
Mar 23, 2009, 01:08 PM
So would the I/I0 become just and I?

ebaines
Mar 23, 2009, 01:56 PM
I don't follow you. In the equation I gave you c = (I/Io)