Consider a tank made of glass (refractive index 1.5) with a thick bottom. It is filled with a liquid of refractive index . A student finds that, irrespective of what the incident angle
(see figure) is for a beam of light entering the liquid,the light reflected from the liquidglass interface is never completely polarized. For this to happen,the minimum value of
is :
Critical angle -
= Refractive index of rarer medium / Refractive index of denser medium =
- wherein
When angle of incidence of a travelling from a dence medium to rarer medium is greater than critical angle, no refraction occurs.
C < ib
ib brewster angle
C critical angle
sin C < sin ib
For air liquid
sin 90 = sin C
since tan ib =
sin C < sin ib
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Why are we applying sin90= u rel c for air liquid interference
Shouldn't we apply critical angle theory for liquid glass interference
And another thing a ray suffers tir only when it travels from denser to rarer medium
That clearly means density of liquid must be greater than 1.5
Plz help