Question

Consider a ray of light incident from air onto a slab of glass (refractive index n) of width d, at an angle $\theta$ The phase difference between the ray reflected by the top surface of the glass and the bottom surface is

• A. $\frac{4\pi d}{\lambda}\left( 1 - \frac{1}{n^{2}}\sin^{2}\theta \right)^{1/2} + \pi$
• B. $\frac{4\pi d}{\lambda}\left( 1 - \frac{1}{n^{2}}\sin^{2}\theta \right)^{1/2}$
• C. $\frac{4\pi d}{\lambda}\left( 1 - \frac{1}{n^{2}}\sin^{2}\theta \right)^{1/2} + \frac{\pi}{2}$
• D. $\frac{4\pi d}{\lambda}\left( 1 - \frac{1}{n^{2}}\sin^{2}\theta \right)^{1/2} + \pi$

Answer 1

Answer: (A)

$\frac{4\pi d}{\lambda}\left( 1 - \frac{1}{n^{2}}\sin^{2}\theta \right)^{1/2} + \pi$

Answer 2

: $\frac{4\pi d}{\lambda}\left( 1 - \frac{1}{n^{2}}\sin^{2}\theta \right)^{1/2} + \pi$