[AlexandraHealy]

I am trying to research the attenuation of light through colored liquids, in particular Ribena. I used a colorimeter with varying Ribena concentrations and a steady pH value to gain some absorbency values. I am struggling to find a relationship between absorbency and attenuation. I would like to convert the absorbency values I have collected into a way in which I can apply the formula I=I0e-ux. This will allow me to investigate the relationship between the attenuation co-efficient and the concentration of Ribena.
Thank-you!
Alexandra

[Capuchin]

I'm not entirely sure where you're having the problem here, can you elaborate? :)

Attenuation is just the measure of the amount of light that is not transmitted. i.e. it is the amount of light that is both reflected or absorbed.

[AlexandraHealy]

You've pretty much answered my question there. :)
I have collected absorbency values and hit a brick wall because I wasn't sure how to convert that to attenuation but if they're the same thing I should have no problem, right?
So if I wanted to find the attenuation co-efficient, I could just plug in an absorbency value for I?
Thanks again

[Capuchin]

Well, in the equation you have given there, I=I0e-ux

I would assume that I is the intensity of light transmitted after passing through a thickness of material x, with attenuation coefficient u and original light intensity I0.

[AlexandraHealy]

Yes I think that's pretty accurate. So, in saying that, are the values I collected for absorbency pointless? Should it have been the intensity of light not passing through the sample I've measured?
Forgive me, I'm struggling to grasp how I could put say a value of 1.2A for absorbency from the colorimeter and compare it with concentration.