A fish in an aquarium approaches the left wall at a rate of `3ms^(-1)` observes a fly approaching it at `8ms^(-1)`. If the refractive index of water is `(4//3)`, find the actual velocity of the fly.

A fish rising vertically to the surface of water in a lake uniformly at the rate of 3ms^(-1) observes a bird diving vertically towards the water at a rate of 9ms^(-1) vertically above it. If the refractive index of water is 4/3 the actual velocity of the dive of the bird is (in ms^(-1) )

Speed of light in glass is 2xx 10^(8) ms^(-1) . Find the refractive index of glass.

Find the refractive index of water with respect to glass if the refractive index of water is 4/3 and the refractive index of glass is 3/2.

The radius of the light circle observed by a fish at a depth of 12 meter is (refractive index of water = 4/3)