Question

Suppose these waves represent the sound of a siren on a passing ambulance. Which wave represents the sound of the siren after it has passed you? Explain your answer.
The wave A has a higher frequency and wave B has a lower frequency.

I REALLY need help. Please.

Answer 1

The answer is wave B has a lower frequency.  Suppose these waves represent the sound of a siren on a passing ambulance. Wave B (lower frequency) represents the sound of the siren after it has passed you.  The ambulance moving towards the observer produces a higher than normal frequency, and the ambulance moving away produces a lower than normal frequency.

Answer 2

Answer:

The correct answer is "wave B has a lower frequency."

Explanation:

The Doppler effect is defined as the change in apparent frequency of a wave produced by the relative movement of the source with respect to its observer. In other words, this effect is the change in the perceived frequency of any wave movement when the sender and the receiver, or observer, move relative to each other.

This is the effect that occurs in this case. And it is explained as follows: When the ambulance approaches the observer, the wave "compresses", that is, the wavelength is short, the frequency high and, therefore, the tone of the perceived sound will be sharp. On the other hand, when the ambulance moves away from the observer, the wave "decompresses", that is, the wavelength is long and the frequency low.

Then the correct answer is "wave B has a lower frequency."