Juan is standing on the street. an ambulance moves toward him and then passes by. what best describes the pitch that juan hears? the pitch remains constant as the ambulance moves toward and then away from juan. the pitch increases and decreases in a repeated pattern as the ambulance passes juan. the pitch drops to a lower pitch once the ambulance passes by juan. the pitch increases to a higher pitch once the ambulance passes by juan.

The correct answer is "the pitch drops to a lower pitch once the ambulance passes by Juan".

Explanation:

Doppler effect is the phenomenon in which there is an increase or decrease in the frequency when there is relative motion between the source and listener.

Pitch depends on the frequency. if the frequency increases then pitch increases.

When the source and the listener are moving towards each other then there is increase in the frequency. When the source and the listener are moving away each other then there is decrease in the frequency.

In the given problem, Juan is standing on the street. An ambulance moves toward him and then passes by the pitch drops to a lower pitch once the ambulance passes by Juan.

C) The pitch drops to a lower pitch once the ambulance passes by Juan.

Explanation: