Use the Law of Malus!
I = I_o cos ^2 (theta)
so for part c it will be
.4 = .5 cos^2 (theta)
But you have to do 90-theta to get the real value. You can draw a diagram and you can see that doing arccos will give you the wrong angle value.
Part d you can do the law of malus again!
I2=...
I figured it out. changing the concentration by half changes the angle by half. So using the law of Malus I do:
I2= ½(I0)cos2((90- (answer to part c/2)
Solving that gives me the right answer.
Homework Statement
The sugar concentration in a solution (e.g., in a urine specimen) can be measured conveniently by using the optical activity of sugar and other asymmetric molecules. In general, an optically active molecule, like sugar, will rotate the plane of polarization through an angle...