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For total internal reflection to occur, the angle of incidence (i) must exceed the critical angle (ic), meaning sin(i) must be greater than sin(ic). Which of the following is correct?

1. sin 45° is greater than 1 divided by the refractive index (μ).
2. The refractive index (μ) is greater than the square root of 2, approximately 1.414.
3. Since the refractive indices of green and violet light are higher than 1.414, they will undergo total internal reflection, while red light will pass through.
4. None of the above statements are correct.

Correct answer: Since the refractive indices of green and violet light are higher than 1.414, they will undergo total internal reflection, while red light will pass through.

Solution

Total internal reflection occurs when the incident angle exceeds the critical angle, and the refractive index plays a key role. Since green and violet light have higher refractive indices (μ > 1.414), they satisfy the condition for total internal reflection, while red light, with a lower refractive index, will be refracted.

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