Question

The rhinestones in costume jewelry are glass with index of refraction 1.50. To make them more reflective, they are often coated with a layer of silicon monoxide of index of refraction 2.00. What is the minimum coating thickness needed to ensure that light of wavelength 480 nm and of perpendicular incidence will be reflected from the two surfaces of the coating with fully constructive interference?

Answer 1

Answer:

60

Explanation:

According to the given question, the computation of minimum coating thickness is shown below:-

The condition for constructive interference is

$2t_{min} = (m + \frac{1}{2} )\times \frac{\lambda}{^nmateral}$

$= (0 + \frac{1}{2} )\times \frac{\lambda}{^nmateral}$

$t = \frac{\lambda}{4n}$

Now we will put the values to the above formula to reach the answer

$= \frac{480nm}{4\times 2.0}$

= 60

Therefore we simply applied the above formula to determine the minimum coating thickness