Same chapter3 marksDifficulty: Medium
A tank is filled with water to a depth of 40 cm. If the refractive index of water is 4/3, find the apparent depth of the tank.
Refraction of Light at Plane Surfaces
3 marksDifficulty: Medium
State the two conditions necessary for total internal reflection to take place.
Original Khojo Papers practice question — not from a past board paper.
Answer
The light must be travelling from an optically denser medium into an optically rarer medium, and the angle of incidence in the denser medium must be greater than the critical angle for that pair of media.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
If either condition fails, part of the light is refracted out and only part is reflected.
Related questions
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Refraction of Light at Plane Surfaces
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Refraction of Light at Plane Surfaces
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Refraction of Light at Plane Surfaces