Calculate Brewster Angle & Significance for Light in Ethanol-Crown Glass

[Shaley]

light travels from ethanol intro crown glass. what's the brewster angle in this situation? illustrate your answer with a light ray diagram. what's the signifcance of this angle of incidence?

n1=1.36for ethanol
nR=1.52 for crown glass

tanangleB=nR/ni
=1.52/1.36
=1.12 (48.2 degrees)

the only thing that I have in the diagram is the face that both the incident and reflected rays are 48.2 degrees in the ethanol..not even sure if that is right.

not sure how to draw it or what the signicance is...please explain.

 

[Matterwave]

The Brewster's angle is the incident angle at which only S-polarized light is reflected. Therefore, the reflected beam is S-polarized, while the refracted beam has both S and P polarizations.

The point is that the Brewster's angle only gives you the angle of incidence, and not the angle of reflection or angle of refraction. To get those two angles, you need to apply the known reflection and refraction rules.

Reflection is easy. Refraction requires Snell's law.

 

[kerimek]

The Brewster angle is defined as the angle of incidence at which the reflected light is completely polarized, meaning that the electric field vector of the reflected light is perpendicular to the plane of incidence. In this situation, the Brewster angle between ethanol and crown glass is 48.2 degrees.

To illustrate this angle, we can draw a light ray diagram. The incident light ray from ethanol enters the crown glass at an angle of 48.2 degrees to the normal. At this angle, the reflected ray will be completely polarized and will be reflected at an angle of 90 degrees to the normal. This means that the reflected ray will be parallel to the surface of the crown glass.

The significance of this angle of incidence is that it can be used to determine the refractive index of the crown glass. By measuring the angle of incidence at which the reflected light is completely polarized, we can use the formula tan(angleB) = nR/ni to calculate the refractive index of crown glass. This angle is also important in applications such as polarizing filters and anti-reflective coatings, where it is used to control the polarization of light.