Question

what is critical angle

Answer 1

The critical angle is defined as the angle of incident that provides and angle of refraction of 90 degree

Answer 2

Hi friend,
Critical angle is angle at which angle of refracted ray becomes 90°.Critical angle is formed when ray travels from denser to rarer medium and ray graces at interface of denser and rarer medium and it will not enter in rarer medium as angle of refracted ray is 90⁰.
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