A sound technician is testing the sound acoustics in a theatre for an upcoming music concert. As he moves towards the speakers, he notices the pitch of the music gets higher. Which description best explains why the pitch gets higher as the technician moves toward the speakers?

Diffraction between speakers
Interference of sound waves
Increase in sound wavelengths
Increase in wave frequency

When we talk about acoustics we are dealing with sound waves, and one of their main components along with the velocity and wavelength is the frequency.

In this sense, the frequency of any wave refers to how fast (or slow) a wave oscillates. For example, in the especific case of sound waves when the oscillation is faster, the frequency is higher and the pitch gets higher as well.

Answer Link

facundo3141592 facundo3141592 · Answer 2 · 2019-12-01T19:01:27+01:00

Answer: Option 4, increase in wave frequency.

Explanation: As the technician approaches the speakers, he "feels" the waves with a bigger frequency, this is because of the doppler effect.

This happens because his movement is in the opposite direction of the soundwave, and if we step in his point of view, he sees the soundwaves moving faster towards him. This causes an increase in the frequency that he feels, and as we know, as higher is the frequency of a soundwave, higher is the pitch of the soundwave.

so the right option is the 4 one, increase in wave frequency.