Question

What do you understand by interference of light? Two waves with
amplitudes a, and an and angular frequency w are imposed. Find
the intensity in case of constructive interference and destructive
interference.​

Answer 1

Interference of light :

Explanation:

Interference is that the phenomenon during which two waves superpose to form the resultant wave of the lower, higher, or same amplitude.

The most ordinary seen interference is optical interference or light interference.

This means that light waves initiating out of a source do not have a constant amplitude, frequency, or phase.

It has two forms: 1) Constructive interference

                           2) Destructive interference

The intensity of light in the constructive interference :

The intensity of light in the constructive interference pattern is

I = $\displaysyle I = I_0cos^2\phi$

where

$I_0$ = intensity at the central fringe

φ = phase difference

The intensity of light in the destructive interference :

Destructive interference occurs when the maxima of two waves are 180 degrees i.e. out of phase.

A positive displacement of one wave is canceled specifically by a negative displacement of the other wave.

The amplitude of the ensuring wave is zero. The dark regions occur when the waves are destructively interfere.

Hence the intensity of light at destructive the interference is zero.

i.e. I = 0