PROPERTIES OF LIGHT

I. Since light is a transverse wave, it can be polarized.

  A. Most common sources emit light that is unpolarized; the direction of the electric field vector is always perpendiculaar to   the direction of travel, but its direction changes randomly.

  





  B. Polarizing materials typically absorb E-fields oscillating in all directions except one (the polarizing direction) and transmit   the E-field in that direction.

   1. The intensity of the emerging linearly polarized light is then I = (1/2)I0 where I0 is the incoming intensity.




   2. If this linearly polarized light passes through a second polarizer, then only the component in the polarizing direction of the    polarizing sheet is transmitted.

    (a) How does the transmitted intensity depend on the angle between the E-vector and the polarizing direction?







II. Geometrical optics - plane surfaces

  A. What is the law of reflection?





  B. What is the law of refraction?






  C. What is the index of refraction?

   1. What is chromatic dispersion?






  D. What is total internal reflection?

   1. Under what conditions can it occur?

  





   2. What is the critical angle?









III. What is Brewster's angle and how is it related to reflection and polarization?




EXAMPLES

Text Ch. 34: Problem 56