A fish is vertically below a flying bird moving vertically down toward water surface. The bird will appear to the fish to be

Explanation

When the bird sees the fish:
The fish and the bird are shown in the following figure along with the corresponding coordinate system. A ray of light now travels from the fish, through water, across the interface, through air and reaches the birs. Here, medium 1 is water and medium 2 is air.
` d_(1)=-60 cm, mu_(1)=(4)/(3), mu_(2)=1`
As `(mu_(1))/(d_(1))=(mu_(2))/(d_(2)) or d_(2)=(mu_(2))/(mu_(1))d_(1)` , we get
`d_(2)=-45 cm`
Thus, the fish appears to be 45 cm below the water-air interface. Image of fish is formed at I.
When the fish sees teh bird:
The fish and the bird are shown in the following figure along with the corresponding coordinate system. A ray of light now travels from the bird, through air, across the interface, through water and reaches the fish. Here, medium 1 is air and medium 2 is water.
`d_(1)=+120cm, mu_(1)=1, mu_(2)=(4)/(3)`
As `(mu_(1))/(d_(1))=(mu_(2))/(d_(2))` or `d_(2)=(mu_(2))/(mu_(1))d_(1)` we get `d_(2)=160 cm`
Thus, the bird appears to be 160 cm above the water-air interface. Image of bird is formed at I.