Define the critical angle for a given pair of media and total internal reflection. Obtain the relation between the critical angle and the refractive index of the medium.
Solution
\textbf{Critical angle} (): the angle of incidence (in the denser medium) at which the refracted ray just grazes the surface, i.e. the angle of refraction is .
\textbf{Total internal reflection:} when the angle of incidence in the denser medium exceeds , no refraction occurs and all the light is reflected back into the denser medium.
Applying Snell's law (denser rarer) at the critical angle:
\textbf{Total internal reflection:} when the angle of incidence in the denser medium exceeds , no refraction occurs and all the light is reflected back into the denser medium.
Applying Snell's law (denser rarer) at the critical angle:
CBSE Class 12 Board · 2023 · Subjective