A police car is parked by the side of a highway and its siren emits a sound measuring 750 Hz. As you approach the police car from a distance, you hear a change in the sound. The change is in the sound's A) frequency. B) pitch and frequency. C) frequency and wavelength. D) pitch, intensity, and loudness.
This is called the Doppler effect. It's essentially a compression of the sound wave. When the sound wave compresses, the wavelength is therefore decreased. Becasue frequency is inversely related to the wavelength, the frequency is changed as well.
F = v/λ
F - frequency
v - velocity
λ - wavelength
Answer:
D) pitch and frequency
Step-by-step explanation:
If it's USATestprep it's D I just answered this one.