10-4 W/m2 how do you get that in decibel if the start is I0= 10 -12 W/m2 L=10*log(I/I_0 ) [dB] L=10*log(I/I_0 ) [dB]
10-4/10-12 → 108
L = 10*log10(108) → 10*8 or L = 80 dB
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