GEOLOGY
PHYSICAL MINERALOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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retardation
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befrings
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double refraction
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None of the above
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Detailed explanation-1: -In crystal optics, the amount by which the slow wave falls behind the fast wave during passage through an anisotropic crystal plate.
Detailed explanation-2: -Birefringence is a measure of the differential RI. Therefore the greater the BIREFRINGENCE of a mineral, the greater the RETARDATION. The further light must travel through an anisotropic grain the more the slow ray will lag behind. Thus the greater the THICKNESS of the sample, the greater the RETARDATION.
Detailed explanation-3: -Obviously, the greater the thickness or difference in refractive indices, the greater the degree of retardation between waves.
Detailed explanation-4: - = t(N-n), the retardation or path difference produced during passage through the crystal, and.