INTERESTED IN THE EXPLANATION, NOT THE ANSWER!!! 10. In the figure below unpolar

Question

INTERESTED IN THE EXPLANATION, NOT THE ANSWER!!!

10. In the figure below unpolarized light is incident on polarizer A and the light then passes through polarizers B and C before exiting the optical system to the right. Polarizer A is aligned vertically, polarizer B is aligned at an angle ? with respect to the vertical axis and polarizer C is aligned horizontally or 90° with respect to polarizer A. Which value of ? (i.e. the angle of polarizer B) allows the maximum intensity of light to pass through the optical system? A. 0o B. 45o C. 60o D. 90o E. No light is transmitted through the system.

Explanation / Answer

in the iven problem the first and last polarizers are oriented at 90 degrees to each other, say second polarizer has its polarization axis rotated an angle of phi from the first polarizer.
then the third polarizer is rotated an angle of (pi/2 - phi) from the second polarizer.

   let I1 is intensity after passing through first polarizer and
        I2 is = I1 cos^2 phi

   intensity after third polarizer is I3
   I3 = I2 cos^2 (pi/2 - phi)= I1 (cos^2phi)(cos^2(pi/2 - phi))

   then above equation can be written as I3 = I1/4 sin^2 (2phi)

   C is alligned horizontally so here theta is zero then angle phi = 45 + theta ==> phi = 45 degrees

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.