Refraction at a curved surface: A fisherman in a stream 39 cm deep looks downward into the water and sees a rock on the stream bed. How deep does the stream appear to the fisherman? The index of refraction of the water is 1.33.

Question

Quizplus · Accepted Answer

The apparent depth can be calculated using the formula $d' = \frac{d}{n}$, where $d'$ is the apparent depth, $d$ is the real depth, and $n$ is the index of refraction of water. Substituting the given values, $d' = \frac{39\, \text{cm}}{1.33} \approx 29\, \text{cm}$.

Refraction at a Curved Surface: a Fisherman in a Stream