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प्रश्न
Greenlight is an incident at the polarising angle on a certain transparent medium. The angle of refraction is 30°.
Find
(i) polarising angle, and
(ii) refractive index of the medium.
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उत्तर
(i) when the light is incident at the polarizing angle, the angle of refraction and angle of polarization are related according to the equation,
∠ip + ∠r = 90°
The angle of refraction is given as, 30°. So the angle of polarization, ∠ip = 90° - 30° = 60°
(ii) Applying Snell's law, we can write, the refractive index of the transparent media,` mu = sin"i"_"p"/sin "r"`
⇒ `mu = sin60^@/sin30^@ = (sqrt3/2)/(1/2) = sqrt3`
⇒ ` = mu sqrt3`
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