What is the wavelength of the light entering an interferometer if 402 bright fringes are counted when the movable mirror moves 0.115 mm?

Question

asked Sep 16, 2021 215k views

1 Answer

Suamikim · Answer 1 · 2021-09-22T16:38:19+0000

Answer:

The value is
$\lambda = 572 *10^(-9) \ m$

Step-by-step explanation:

From the question we are told that

The number of bright fringes is n = 402

The displacement of the mirror is
$\delta l = 0.115 \ mm = 1.15 *10^(-4) \ m$

Generally the number of fringes is mathematically represented as

$n = (2 * \delta l )/(\lambda )$

=>
$\lambda = (2 * \delta l )/(n )$

=>
$\lambda = (2 * 1.15*10^(-4) )/(402 )$

=>
$\lambda = 572 *10^(-9) \ m$