A student very cautiously traces the path of a ray through a glass slab for different values of the angle of incidence `(/_i)`. He then measures the corresponding values of the angle of refraction `(/_r)` and the angle of emergence `(/_e)` for every value of the angle of incidence. On analysing these measurements of angles, his conclusion would be

Options

A. `/_i gt /_r gt /_e`
B. `/_i= /_e gt /_r`
C. `/_i lt /_r lt /_e`
D. `/_i= /_e lt /_r`

Answer

B

Explanation

(b) The correct path of a ray through a glass slab is shown in Fig. As net deviation through the glass slab is zero, therefor `/_i = /_i`. At `B`, the ray goes from a rarer to a denser medium, bends towards normal. Therefore `/_r lt /_i`.
or `/_i gt /_r`
Hence we conclude that `/_i=/_e gt /_r`.