I need help with the question attached. From my understanding, the equation (I = I0e^(–µx)) is used to measure absorption, which is what the question asks for. So I did e^(-0.96x2.3) and got 0.11. But got the answer wrong...
Does this mean that (e^(–µx)) is always the fraction that is transmitted? (never absorbed, despite the attenuation coefficient)?
Yes, that's correct. If you think about the behaviour as thickness (x) gets large, it makes sense: I/I0 goes to zero as x becomes large, which must refer to the fraction transmitted (and thus the fraction absorbed is 1 minus the fraction transmitted.