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प्रश्न
Discuss polarisation by selective absorption.
उत्तर
- Selective absorption is the property of a material which transmits waves whose electric fields vibrate in a plane parallel to a certain direction of orientation and absorbs all other waves.
- The polaroids or polarisers are thin commercial sheets which make use of the property of selective absorption to produce an intense beam of plane polarised light.
- Selective absorption is also called as dichroism.
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संबंधित प्रश्न
Why does an unpolarised light incident on a polaroid get linearly polarised ?
How does one demonstrate, using a suitable diagram, that unpolarised light when passed through a Polaroid gets polarised?
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Find
(i) polarising angle, and
(ii) refractive index of the medium.
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