Chapter 31, Problem 10A

To determine

To Explain: The condition required for part of the light reflected from a surface to be canceled by another part that is reflected from a second surface.

Answer to Problem 10A

When maxima of two waves are out of phase of 180 degrees then destructive interference occurs.

Explanation of Solution

Introduction:

During the superimposing of two waves in destructive interference, the waves cancel each other out, creating a lower amplitude resultant wave.

A part of the light reflected from a surface is canceled by another part that is reflected from a second surface when the waves are out of the phase. It means that the crest and troughs of the waves are superimposed.

Conclusion:

Thus, destructive interference occurs when waves are out of phase.