Three polarizing plates are to be placed along a common optical ...

[gbarreiro]

Three polarizing plates are to be placed along a common optical axis. The last plate is oriented so that its plane of polarization is 90 from the plane of polarization of the first plate. In between these two plates, the third plate is placed with its plane of polarization making an angle of 45 with respect to the plane for the first and last plate? If unpolarized light intensity l0 is sent into the first of these plates, what is the intensity emerging from the last plate? In the figure, 1 = 0, 2 = 45, and 3 = 90.
 
Question 2

Which of the following does not describe a method of achieving polarization?
  1.Light hits a reflective surface at a particular angle, dependent on wavelength and index of refraction. The light which reflects is polarized in one direction, and the light which is transmitted is polarized perpendicular to the reflected light.
  2.Unpolarized light encounters material made of parallel long-chain molecules. The portion of the light in line with the chains is transmitted; the rest is absorbed.
  3.Light collides with air or other gas molecules, which absorb the energy. Electrons inside the molecule begin to vibrate, emitting polarized light much like a radio antennae.
  4.Light is sent through an optically active material.

[tdewitt]

Answer to Question 1

4

Answer to Question 2

4

[gbarreiro]

Excellent

[emsimon14]

Thanks for the timely response, appreciate it