A coin is placed at the bottom of a beaker filled to a depth of with a transparent oil
PHYSICS · Subjective · CBSE · Physics · Light — Reflection and Refraction · Light — Reflection and Refraction
Problem
A coin is placed at the bottom of a beaker filled to a depth of 15cm with a transparent oil. An observer looking vertically down from above sees the coin at an apparent depth of 10cm.
(i) Explain why the coin appears to be at a shallower depth than its actual depth.
(ii) Define the term ‘refractive index’ of a medium with respect to air.
(iii) Using the data given, calculate the refractive index of the oil.
(iv) If the same observer replaces the oil with water to the same depth, predict qualitatively whether the coin will now appear higher or lower than before and justify your answer.