What is the thinnest soap film (excluding the case of zero thickness) that appears black when illuminated with light with a wavelength of 555 nmnm

Respuesta :

Answer:

The minimum thickness of soap film is [tex]2.086\times 10^{-7} m[/tex].

Explanation:

wavelength = 555 nm

refractive index, n = 1.33

For the destructive interference,

the thickness is given by

[tex]t =\frac{m \lambda }{2 n}[/tex]

Here, m is the order, n is the refractive index and [tex]\lambda[/tex] is the wavelength.

For minimum thickness, m = 1

So the thickness is  

[tex]t =\frac{1 \times 555\times 10^{-9} }{2 \times 1.33}\\\\t = 2.086\times 10^{-7} m[/tex]