Q26 of 27 Page 132

Suppose you are inside the water in a swimming pool near an edge. A friend is standing on the edge. Do you find your friend taller or shorter than his usual height? Why? (A S7)

Using refraction for plane surfaces: n2/v = n1/u

n1 = refractive index of air = 1


n2 = refractive index of water = n


let x be the actual height of my friend and y be the apparent height.



As the refractive index of water is greater than 1, therefore y is greater than


x which implies that apparent height is greater than the actual height.


As light travels from denser to rarer medium, the light rays bend away from
the normal due to refraction and the speed of light also changes in two
mediums due to refraction.


So my friend will appear taller if I see him while inside the water.


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