# Reflection and Transmission Intensity of randomly polarised light

1. Apr 18, 2012

### Anonymous00

1. The problem statement, all variables and given/known data
A randomly polarized beam of light hits a water surface at Brewster angle. What is the intensity of the transmitted and reflected beams? The refractive index of water is n = 1.33

2. Relevant equations

3. The attempt at a solution
Since the light is randomly polarised, it should have equal electric field amplitudes in all directions? Am I supposed to sum up the electric fields along the p polarisation and s polarisation axis before using fresnel equations to calculate the intensity?

2. Apr 18, 2012

### rude man

Light incident on the water surface is not randomly polarized in all directions. There is no component along the direction of the beam.

First thing is to find out what kind of light is reflected at the Brewster angle. Look into your textbook.

3. Apr 18, 2012

### sunjin09

At brewster angle TM mode (50% intensity) is not reflected. So the reflection is only TE, and reflection coefficient is given by Fresnel's formula.