An ambulance emits a frequency of 450 Hz from its siren. What frequency is heard by a man as the ambulance moves toward him?

As the ambulance moves toward the man, each successive sound wave is emitted from a position closer to him. This compresses the waves, shortening their wavelength and increasing the frequency he hears above the siren’s emitted frequency of 450 Hz. Therefore, the heard frequency is more than 450 Hz.

AI-written and checked against the verified answer.