A fish and bird are moving as shown in figure. Find the velocity of bird as observed by fish.

Question

G1 Physics · Accepted Answer

Derived solution: Step 1: Use Snell’s law at each plane interface. For paraxial viewing through a plane surface, apparent depth = real depth × n(observer)/n(object medium). Step 2: Substitute the values given in the question and apply the geometry/sign convention shown. Step 3: On simplification the result is 8 m s⁻¹. Therefore the correct option is A.