Question

Calculate the thickness of water film
whose refractive index is 1.33 , formed on
a glass window - pane which acts as an
anti reflection coating . Given 1= 5500 Å
Answer
A.O 2894 Å
B.O 8094 Å
C.O 5033 Å
D.O 1033 Å​

Answer 1

Answer:

c. as the answer says along

Answer 2

Answer:

The thickness of the water film, t, measured is $1033.8\AA$ ≈ $1033\AA$.

Therefore, option d) $1033\AA$ is correct.

Explanation:

Given,

The refractive index of water film, μ = $1.33$

The wavelength of the water film, λ = $5500\AA$

The thickness of the water film, t =?

Now, we have to find out the thickness of the water film by using the formula given below:

• $2\mu t = \frac{\lambda}{2}$
• t = $\frac{\lambda}{4\mu}$

After putting the given values of λ and μ in the equation, we get:

• t = $\frac{5500}{4\times1.33}$
• t = $1033.8\AA$ ≈ $1033\AA$

Hence, the thickness of the water film, t =  $1033.8\AA$ ≈ $1033\AA$.