# Homework Help: Polarization by reflection

1. Mar 5, 2012

### squirrelly

1. The problem statement, all variables and given/known data

As the sun rises over a still pond, an angle will be reached where its image seen on the water's surface(n=1.33) will be completely polarized in a plan parallel to the surface.

i) Compute the appropriate incident angle(that is the polarization or Brewster's angle)

ii)At what angle(from the normal) will the transmitted beam propagate through the water(that is, what is the angle of refraction)

iii)What is the angle between the reflected and refracted beams.

3. The attempt at a solution
i) n2cos(θo)-n1√[(1-(n21/n22)sin2o)]

(n22/n21)=tan2o)+1-(n21/n22)tan2o)

tan2o)={[(n22/n21-1]/[1-(n21/n22)]}=(n22/n21)

tan(θo)=(n2/n1)=(1.33/1)

θo=tan-1(1.33)=53°
1. The problem statement, all variables and given/known data

and that's as far as I could get. :/ Im pretty sure part(i) is right.

2. Mar 5, 2012

### SammyS

Staff Emeritus
Hello squirrelly. Welcome to PF !

ii) Use Snell's Law to find the angle of refraction.

iii) Draw a sketch. Use geometry.