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LDRs and intensity

eptheta

Dec 20, 2009
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Dec 20, 2009
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I am slightly confused.
I was doing a little experiment where I passed red light through a blue/purple solution and measured the light intensity at the other end using an LDR.

I varied concentration and got all the data i needed.
I wish to see how concentration affects light intensity by plotting a graph between resistance and concentration, however, I can't figure out how to use resistance correctly.
I know that concentration and light intensity are anyway a lograthmic relation(Beer Lambert's law)
-log(I/Io) (proportional to) conc

What is the relationship between resistance and intensity? Is it a log function as well ? The datasheet it shows this:
95421386.jpg

Am i getting the units wrong or something ?

Thanks

EDIT: sorry if the graph isn't clear, you can look at the datasheet yourself
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Jan 21, 2010
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Wow. Looks like a perfect log/log relationship.
 

eptheta

Dec 20, 2009
188
Joined
Dec 20, 2009
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188
Oh God I'm stupid. Sorry, didn't see the scale, just the units. I expected to see log(R) and log(I).
In my defense, I posted this around 3:00 am.
 
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