A sound of constant frequency is produced by the siren on top of a firehouse. Compared to the frequency produced by the siren, the frequency heard by the fire fighter approaching the fire house is what?
To determine the frequency heard by the fire fighter approaching the firehouse, we need to consider the concept of the Doppler effect. The Doppler effect describes the change in frequency of a wave (such as sound) relative to an observer moving relative to the source of the wave.
In this case, as the fire fighter is approaching the firehouse, they are moving towards the source of the sound (the siren). According to the Doppler effect, when an observer approaches a sound source, the perceived frequency of the sound is higher than the actual frequency emitted by the source.
Therefore, the frequency heard by the fire fighter approaching the firehouse will be higher than the frequency produced by the siren.
you might try googling
doppler effect