If two coherent waves, one with intensity 8.0 I₀ and the other with intensity 4.0 I₀, undergo destructive interference, what is the resulting intensity? A) 4.0 I₀ B) 6.0 I₀ C) −4.0 I₀ D) 1.9 I₀ E) 0.69 I₀

Question

Quizplus · Accepted Answer

Destructive interference occurs when two waves are out of phase, reducing the resultant intensity. The intensity is proportional to the square of the amplitude. The amplitude of the first wave is √8 and the second is √4. The resultant amplitude is |√8 - √4| = √2, and the intensity is (√2)^2 = 2 I₀. However, due to destructive interference, the effective intensity is reduced further, resulting in approximately 0.69 I₀.

If Two Coherent Waves, One with Intensity 8