A fish in water (refractive index n ) looks at a bird vertically above in the air. If y is the height of the bird and x is the depth of the fish from the surface, then the distance of the bird as estimated by the fish is

Step-by-step solution

When object is in rarer medium and observer is in denser medium Normal shift, d =( n -1) h where h= real depth Here, h=y Now, apparent depth or the apparent height of the bird from the surface of the water = y +( n -1) y = ny . The total distance of the bird as estimated by fish is x+n y .