(A) (a) Observe the following diagram and compare (i) speed of light and (ii) optical densities of the three…
(A) (a) Observe the following diagram and compare (i) speed of light and (ii) optical densities of the three media A, B and C. Also give justification for your answer of any one of the two cases in terms of refractive indices of A, B and C.
(b) Redraw the path of a ray of light through the three media, if the ray of light starting from medium A falls on the medium B
(i) Obliquely and the optical density of medium B is made more than that of A and C.
(ii) The ray falls normally from medium A to medium B.
Solution
(A)(a)(i) Speed of light in A and B is same whereas the speed of light in C is greater than that of A and B.
(ii) Optical density of A and B is same whereas optical density of C is less than that of A and B.
Since the ray of light does not bend while passing from A to B the refractive indices of A and B are same and since it bends away from the normal while passing from B to C the refractive index of C is less than that of A and B. / Refractive index of a medium is inversely proportional to the speed of light in that medium.
(b) (i) Oblique Incidence
[Diagram: ray refracting through rectangular slab layers A, B, C]
(ii) Normal Incidence
[Diagram: ray passing straight through rectangular slab layers A, B, C]
