How Do Radio Waves Attenuate in Water Over Distance?

krickette
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Homework Statement



What is the percentage amplitude reduction of 10MHz radio waves that travel through 250 meters of water? Construct a plot of the average energy per unit volume stored in these radio waves as a function of depth from 0 to 250 meters in terms of the initial electric field at 0 meters depth. Be sure to include the equation that you plot.

Homework Equations



I know that it's going to end up being that energy/volume =f(EI) and that we need to find the f.

The Attempt at a Solution


Oh lordie. This problem is really killing me. I mean I am stumped beyond reason, and I know that I could do it if my head were clear, but I have to get this done so I can study for the rest of my finals, and I'm running on like no sleep. I know, I suck. I have literally pages of work for this problem in front of me, but it's all just garbage, so there's no real point in me posting it up here, since it wasn't anywhere close.

Anyway, if someone could help, even just a nudge in the right direction, I'll like, be your friend forever!
 
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krickette said:

Homework Statement



What is the percentage amplitude reduction of 10MHz radio waves that travel through 250 meters of water? Construct a plot of the average energy per unit volume stored in these radio waves as a function of depth from 0 to 250 meters in terms of the initial electric field at 0 meters depth. Be sure to include the equation that you plot.

Homework Equations



I know that it's going to end up being that energy/volume =f(EI) and that we need to find the f.

The Attempt at a Solution


Oh lordie. This problem is really killing me. I mean I am stumped beyond reason, and I know that I could do it if my head were clear, but I have to get this done so I can study for the rest of my finals, and I'm running on like no sleep. I know, I suck. I have literally pages of work for this problem in front of me, but it's all just garbage, so there's no real point in me posting it up here, since it wasn't anywhere close.

Anyway, if someone could help, even just a nudge in the right direction, I'll like, be your friend forever!

You should probably start by reviewing your notes / text on the Beer-Lambert law (and if it's Griffiths, there's a table of absorbancy values somewhere--I suspect the same is true of Jackson):
http://teaching.shu.ac.uk/hwb/chemistry/tutorials/molspec/beers1.htm
 
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