A fish in a pond at a depth of 30 cm looks up at a bird flying at a height of 30 cm above the water surface. What is the apparent distance of the bird as seen by the fish? (Refractive index of water = 4/3)

B. 70 cm — The fish sees the bird through the water surface. The apparent height of the bird is times its actual height above the surface.

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$A fish in a pond at a depth looks up at a bird flying at a height above the water surface. What is the apparent distance of the bird as seen by the fish? (Refractive index of water )$

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Correct answer: B — $70 cm$

The apparent height of the bird as seen by the fish is h^{'} = μ \times h = (4/3) \times 30 cm = 40 cm . The total apparent distance is the depth of the fish plus the apparent height of the bird, which is 30 cm + 40 cm = 70 cm .