(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Some biologically active molecules rotate the direction of polarization of linearly polarized light, either clockwise or anticlockwise. For example, 5 gm of l-leucine dissolved in 100 mL of water causes a rotation by 0.550o while the same concentration of d-glutamic acid causes a rotation of 0.620o. If these solutions are placed between crossed polarizers illuminated by a beam of unpolarized light of intensity I=13 W/m2, what is the intensity of light transmitted by:

(a) the l-leucine solution? ___W/m^2

(b) the d-glutamic acid solution? ___W/m^2

2. Relevant equations

I=Io*cos^2(theta)

I=.5*Io

3. The attempt at a solution

To do this, for each solution, I plugged in the numbers in the equation:

for l-leucine: I=(13 W/m^2)(cos^2(0.62))

for d-glutamate: I=(13 W/m^2)(cos^2(0.55))

That didn't work. So I then tried finding I by doing:

I=(.5)(13)=6.75 then used this is the above equation and tried solving for Io then. That didn't work. A hint or suggestion would be greatly appreciated. Thank you!

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# Intensity of Light by Polarizers

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