A fish, F in the pond, is at a depth of 0.8 m from water surface and is moving vertically upwards with velocity 2 m s⁻¹. At the same instant, a bird B is at a height of 6 m from water surface and is moving downwards with velocity 3 m s⁻¹. At this instant both are on the same vertical lines as shown in the figure. Which of the following statement(s) is(are) correct?

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: Test each statement independently using these relations and the data/figure. Step 3: The statements that satisfy the required optical conditions are B: Depth of F, observed by B (from itself) is equal to 6.60 m.; D: Velocity of F, observed by B (relative to itself) if equal to 4.50 m s⁻¹.. Hence the correct answer is…