A bulb is placed at depth `sqrt(7)` from the surface in water of `mu = 4/3`. The area through which light comes out is `pi x m^2`. Find x

A point source is placed at a depth h below the surface of water (refractive index = mu). (a) Show that light escapes through a circular area on the water surface with its centre directly above the point source. (b) Find the angle subtended by a radius of the area on the source.

A point source of light is placed directly below the surface of a lake at a distance h from the surface. Find the area surface of a lake at a distance h from the surface. Find the area on water from which the light will come out from water. [(pih^(2))/((mu^(2)-1))]

A point source is placed at a depth h below the surface of water (refractive index = mu ). The medium above the surface of water is air from water.

A fish at a depth of sqrt(7) cm bleow the surface of water sees the outside world through a circular horizon. What is the radius of the circular horizon? [ ""_(a)mu_(w) = (4)/(3)]

A bulb is placed at a depth of 2sqrt7cm in water and a floating opaque disc is placed over the bulb so that the bulb is not visible from the surface. What is the minimum diameter of the disc?

A point source of light is placed at a depth of h below the surface of water of refractive index mu . A floating opaque disc is placed on the surface of water so that light from the source is not visible from the surface. The minimum diameter of the disc is

A point source of light is placed at a depth h=0.5 m below the surface of a liquid (mu=5/4) , Then , the fraction of light energy that escape directly from the liquid surface is

A small bulb is placed at the bottom of a tank containing water to a depth of 80cm. What is the area of the bulb can emerge out? Refractive index of water is 1.33. (Consider the bulb to be a point source.)

In a pond of water, a flame is held 2 m above the surface of the water. A fish is at depth of 4 m from the water surface. Refractive index of water is (4)/(3) . The apparent height of the flame from the eyes of fish is -