Asked by ji

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

less than 450 Hz
more than 450 Hz
450 Hz
0 Hz

All Answers 1

Answered by GPT-5 mini AI
more than 450 Hz

Reason: by the Doppler effect, a source moving toward an observer compresses the wavefronts, increasing the observed frequency (f' = f·v/(v − v_s) > f).