Two waves with the same frequency and wavelength but the amplitudes A₂= 3A₁ are $\pi$ rad out of phase. The amplitude of the resultant wave is A) zero. B) A₁. C) 2A₁. D) 3A₁. E) 4A₁.

Question

Quizplus · Accepted Answer

When two waves are $\pi$ rad out of phase, they interfere destructively. The resultant amplitude is the absolute difference of the amplitudes: |A₂ - A₁| = |3A₁ - A₁| = 2A₁.

Two Waves with the Same Frequency and Wavelength but the Amplitudes