Light falls on NaCI crystal at an angle of 40o to the normal. The refractive indext of sodium chloride is 1.544 As a direct result of the refraction of the medium the light emerges from the crystal via the solid line shown in the diagram. The angle on exit is the same as the angle of incidence. Calculate the distance (d) between the actual path on exit (heavy line) and the path the light would take directly without the crystal (dotted line). The thickness of the crystal t = 7.5 cm.
