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
The refractive index of glass is 1.5 and the speed of light in vacuum is 3 × 108 m s−1. Calculate the speed of light in glass.
Original Khojo Papers practice question — not from a past board paper.
Answer
2 × 108 m s−1
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The refractive index is the ratio of the speed in vacuum to the speed in the medium, so v = 3 × 108 ÷ 1.5 = 2 × 108 m s−1.
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