(a) Describe in detail an experiment to find the refractive
index of glass
using real and apparent depth method (4 marks)
(b) The figure above shows a slab of glass of uniform thickness,
lying
horizontally. Above it is a layer of water. A ray of light PQ is
incident
upwards on the lower surface of the glass and is refracted
successively
at A, B, and C, the points where it crosses the interfaces.
Calculate
(i) angle x
(ii) angle y, and
(iii) the refractive index of light passing from the water to glass
(9 marks)
(Refractive index of glass = 3/2 , refractive index of water = 4/3)
(c) Light is incident in a glass material which is to be used to
construct a
fibre optic cable. If the critical angle is 25°, what is the
refractive index?