Two sound waves having the same amplitudes are moving in the same direction are out of phase. The amplitude of the resultant wave is:
Correct answer: A. Zero amplitude
- A. Zero amplitude
- B. The sum of the amplitudes of the two waves
- C. Difference of the amplitudes of the two waves
- D. Double the amplitude of either wave
Explanation
The correct answer is A) Zero amplitude. When two sound waves with identical amplitudes are completely out of phase, they interfere destructively, effectively cancelling each other and resulting in a net amplitude of zero. Option B is incorrect because the sum of amplitudes occurs during constructive interference when waves are in phase. Option C is incorrect because the difference in amplitudes applies when the waves have different amplitudes or are not fully out of phase. Option D is incorrect because doubling of amplitude happens during constructive interference of in-phase waves.
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About Superposition and Interference
Superposition states that overlapping waves produce a resultant displacement equal to the algebraic sum of their individual displacements. Interference covers constructive and destructive interference, phase difference, path difference, coherent sources, and conditions for maxima and minima. It differs from diffraction, which involves spreading around openings or obstacles.
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