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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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संबंधित प्रश्न
Three identical polaroid sheets P1, P2 and P3 are oriented so that the pass axis of P2 and P3 are inclined at angles of 60° and 90° respectively with the pass axis of P1. A monochromatic source S of unpolarised light of intensity I0 is kept in front of the polaroid sheet P1 as shown in the figure. Determine the intensities of light as observed by the observer at O, when polaroid P3 is rotated with respect to P2 at angles θ = 30° and 60°.

Show, using a simple polaroid, that light waves are transverse in nature. Intensity of light coming out of a polaroid does not change irrespective of the orientation of the pass axis of the polaroid. Explain why.
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