total internal reflection + citric angle

define total internal reflection

when the light goes into the median and hits boundary inside the median and the light is reflected inside the median.

define critical angle

A specific angle that makes the light reflect between the two medians

what happens to the light when the incidence angle is equal to the critical angle

light ray gets refracted into the boundaries of the median

what happens to the light when the incidence angle is less than the critical angle

light ray gets refracted but some of it gets reflected

what happens to the light ray the nthe incidence ray is more than the critical angle

light ray will hit the boundary whilst being inside the median and reflect, none of the light gets out of the median. (total internal reflection)

formula for critical angle

sin(critical angle) = 1 / n (refractive index)