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
Why does a coin at the bottom of a beaker of water appear to be raised?
Original Khojo Papers practice question — not from a past board paper.
Answer
Rays of light from the coin bend away from the normal as they pass from water into air. To the eye these rays appear to come from a point higher than the coin, so the image formed is nearer the surface and the coin looks raised.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The apparent depth is the real depth divided by the refractive index of water.
Related questions
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Refraction of Light at Plane Surfaces