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Question
A coin placed at the bottom of a beaker appears to be raised by 4.0 cm. If the refractive index of water is 4/3, find the depth of the water in the beaker.
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Solution
Let Real depth = x
∵ Refracture Index, μ = `"Real depth"/"Apparent depth"`
⇒ `4/3="x"/("x"-4)`
⇒ 4x − 16 = 3x
∴ x = 16 cm.
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