1 Answer
Brewster's Law states that when light is reflected from a surface, the angle of incidence at which the reflected light is completely polarized is called the Brewster angle. At this angle, the reflected light and the refracted light are at right angles to each other.
The law is given by the formula:
\[
\tan(\theta_B) = \frac{n_2}{n_1}
\]
Where:
Key Points:
Example:
If light is incident from air (where \(n_1 = 1\)) on glass (where \(n_2 = 1.5\)), we can use Brewster's Law to find the Brewster angle:
\[
\tan(\theta_B) = \frac{1.5}{1} = 1.5
\]
So, \(\theta_B = \tan^{-1}(1.5)\).
This angle will give the value at which light is completely polarized upon reflection.
The law is given by the formula:
\[
\tan(\theta_B) = \frac{n_2}{n_1}
\]
Where:
- \(\theta_B\) is the Brewster angle.
- \(n_1\) is the refractive index of the first medium (e.g., air).
- \(n_2\) is the refractive index of the second medium (e.g., glass or water).
Key Points:
- At the Brewster angle, the reflected light is fully polarized in a plane perpendicular to the plane of incidence.
- This law is used in various applications like polarizing filters and optical devices.
Example:
If light is incident from air (where \(n_1 = 1\)) on glass (where \(n_2 = 1.5\)), we can use Brewster's Law to find the Brewster angle:\[
\tan(\theta_B) = \frac{1.5}{1} = 1.5
\]
So, \(\theta_B = \tan^{-1}(1.5)\).
This angle will give the value at which light is completely polarized upon reflection.