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A coin lies at the bottom of a tank of water (refractive index n_w). To an observer looking from directly above, the coin appears to be:
AAt the same depth as the real depth
BAt an apparent depth = real depth / n_w (i.e., shallower)
CDeeper than the real depth by a factor of n_w
DAt infinity
Answer & Solution
Correct answer: B. At an apparent depth = real depth / n_w (i.e., shallower)
**Apparent depth = real depth / n** (for near-normal viewing). E.g., a coin at the bottom of a 1.33 m deep water tank appears at depth **~1.00 m**. This is why pools look shallower than they actually are.
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