I need to calculate the intensity of a 10000 lux light source travelling through 3.3 cm of water.(adsbygoogle = window.adsbygoogle || []).push({});

I have attempted to solve this using the equation I=I_{o}e^{-A}where i is the intensity, Io is the initial intensity, A is the absorbance calculated as the water attenuation coefficient times the depth, using the water attenuation coefficient of 0.23222 (this could be wrong?)

This equation can be simplified into I=I_{o}*10^-A

however when i plug my numbers into this i seem to get I=10000*9.9 which means that the intensity has increased tenfold in 3cm of water.

Somthing tells me im wrong...

Any help would be greatly appreciated

P.S. thanks to ehild for last response

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# Homework Help: Calculating intensity

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