Which of the following choices correctly describes the behavior of sound waves when the compressions from one wave overlaps with the rarefaction of another?
(A) A compression interferes constructively with the region of rarefaction, so that the waves reinforce each other. The sound becomes louder under constructive interference.
(B) As the two waves overlap they refract as well, changing speed and direction. The sound does not become louder or quieter when refracting.
(C) A compression interferes destructively with the region of rarefaction, so the waves cancel each other out. The sound becomes quieter under destructive interference.
(D) A compression interferes destructively with the region of rarefaction, so the waves cancel each other out. The sound does not become louder or quieter under destructive interference.
The correct choice that describes the behavior of sound waves when the compressions from one wave overlaps with the rarefaction of another is (C) A compression interferes destructively with the region of rarefaction, so the waves cancel each other out. The sound becomes quieter under destructive interference.
To understand why this is the correct choice, let's break it down:
Sound waves are made up of compressions and rarefactions. Compressions are regions of high pressure where molecules are crowded together, while rarefactions are regions of low pressure where molecules are spread out.
Constructive interference occurs when two waves of the same frequency overlap and their compressions align, resulting in a larger amplitude and therefore a louder sound. This choice is incorrect because it states that the waves reinforce each other and the sound becomes louder, which is not the case when compressions overlap with rarefactions.
Refracting, as described in choice (B), refers to the bending of waves as they pass through different mediums or encounter changes in temperature or pressure. While refraction can occur, it does not affect the loudness or quietness of the sound. Therefore, this choice is also incorrect.
Destructive interference, as described in choice (C), occurs when the compressions of one wave coincide with the rarefactions of another, leading to the cancellation or reduction of the wave's amplitude. As a result, the sound becomes quieter under destructive interference. This is the correct choice.
Similarly, choice (D) states that the waves cancel each other out, but unlike choice (C), it incorrectly suggests that the sound does not become louder or quieter. This is not true because destructive interference causes a reduction in amplitude, resulting in a quieter sound.
In conclusion, when the compressions from one wave overlap with the rarefaction of another, destructive interference occurs, leading to a quieter sound, as described in choice (C).