Respuesta :
I think so it ans wold be d.because if the source approaches the observer more and more wavefront will pass and it get squeezed.so wavelength decreases and frequency increases.
Sound increases in pitch as a sound source approaches you because D. The waves are closer together because the object is moving towards you.
The Doppler effect refers to the change in the frequency of a wave and this can be in relation to the observer who is moving relative to the source of the wave.
It should be noted that when one moves to the source of a sound, the pitch of the sound increases. The reason for this is due to the fact that as the waves are closer together, the object is moving towards the person.
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