As you are moving very quickly toward a speaker emitting a pure tone, which characteristics of the sound get larger? (There may be more than one correct choice.)
A) amplitude
B) frequency
C) loudness
D) period
E) wavelength

Question

Quizplus · Accepted Answer

When moving quickly toward a speaker, the frequency of the sound increases due to the Doppler effect, which can also make the sound appear louder, although loudness is subjective and depends on the listener's perception.

As You Are Moving Very Quickly Toward a Speaker Emitting