Q12DQ - University Physics with Modern Physics

Question

 In using the superposition principle to calculate intensities in interference patterns, could you add the intensities of the waves instead of their amplitudes? Explain.

Step-by-Step Solution

Answer

No, the intensities of waves cannot be added instead of their amplitudes to determine the intensities in interference patterns.

Step 1: Define the principle of superposition.

The principle of superposition states: 

When two or more waves overlap, the resultant displacement at any point and at any instant is found by adding the instantaneous displacements that would be produced at the point by the individual waves if each were present alone.

Step 2: Explain can intensities of the waves added instead of amplitudes to calculate intensities in interference using the superposition principle.

Since the destructive peaks contain zero intensity and interference is the combination of both destructive and constructive patterns.

Hence, the intensities of waves are not used instead of amplitudes of waves to calculate the intensities in the interference pattern.