Question

What is needed for Total destructive interference?

Answer 1

The basic requirement for destructive interference is that the two waves are shifted by half a wavelength. This means that the path difference for the two waves must be: R1 R2 = l /2.

Step-by-step explanation:

Answer 2

Destructive interference occurs when the maxima of two waves are 180 degrees out of phase: a positive displacement of one wave is cancelled exactly by a negative displacement of the other wave. The amplitude of the resulting wave is zero.

Explanation: hope it helps :)