New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    If a medium has a critical angle for total internal

    reflection from the medium to vacuum as 90°, what is the velocity of light in the medium? (Take c = 3.0 × 108 m/s)
    A 3 × 10^2 m/s Correct Answer Incorrect Answer
    B 3 × 10^3 m/s Correct Answer Incorrect Answer
    C 3 × 10^5 m/s Correct Answer Incorrect Answer
    D 3 × 10^8 m/s Correct Answer Incorrect Answer

    Solution

    If c is critical angle then Sin c = [(velocity of light in medium) / (velocity of light in vacuum)] sin 90° = [(v) / (3 × 108)] v = 3 × 108 × 1 v = 3 × 108 m/s

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