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Ray Optics — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsRay Optics1 Mark
Question
Assertion : The images formed by total internal reflections are much brighter than those formed by mirrors or lenses.
Reason : There is no loss of intensity in total internal reflection.
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Answer

(a) In total internal reflection, $100 \%$ of incident light is reflected back into the same medium, and there is no loss of intensity, while in reflection from mirrors and refraction from lenses, there is always some loss of intensity. Therefore images formed by total internal reflection are much brighter than those formed by mirrors or lenses.

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