What frequency did you hear 3 seconds after police pass?

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Homework Help Overview

The discussion revolves around a scenario involving the Doppler effect, specifically related to the frequency of a police siren heard after the police vehicle has passed the observer. Participants are exploring the implications of frequency changes due to motion and the relevant equations involved.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • Participants question the base frequency of the siren and whether the frequency changes as the police vehicle approaches or recedes. There are inquiries about the appropriate Doppler shift equations and the missing context in the original posts.

Discussion Status

The discussion is ongoing, with participants seeking clarification on the correct formula for calculating the Doppler effect and the conditions under which the frequency is perceived. Some guidance has been offered regarding the need for more information and context in the original question.

Contextual Notes

There are indications of missing information regarding the siren's base frequency and the velocities of the source and listener, which are crucial for applying the Doppler effect correctly. Participants express frustration over the lack of detail in the initial posts.

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Homework Statement


The police was headed to a felony and passed you so you stopped. What frequency did you hear 3 second after the police passed you?

Homework Equations


f=1/T

The Attempt at a Solution


f=1/3
f=.33Hz
 
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ThePhysicsXV said:

Homework Statement


The police was headed to a felony and passed you so you stopped. What frequency did you hear 3 second after the police passed you?

Homework Equations


f=1/T

The Attempt at a Solution


f=1/3
f=.33Hz
No.

What is the frequency of the siren? Do you only hear it as it approaches (so Doppler shifted to a higher frequency than its no-movement frequency)? Or do you know what its non-moving base frequency is?

What is the equation for the Doppler shift in frequency versus relevant velocities of the source and listener? You are missing so much from this post. Please fix it...
 
berkeman said:
No.

What is the frequency of the siren? Do you only hear it as it approaches (so Doppler shifted to a higher frequency than its no-movement frequency)? Or do you know what its non-moving base frequency is?

What is the equation for the Doppler shift in frequency versus relevant velocities of the source and listener? You are missing so much from this post. Please fix it...
So what's the correct formula?
 
berkeman said:
No.

What is the frequency of the siren? Do you only hear it as it approaches (so Doppler shifted to a higher frequency than its no-movement frequency)? Or do you know what its non-moving base frequency is?

What is the equation for the Doppler shift in frequency versus relevant velocities of the source and listener? You are missing so much from this post. Please fix it...
Frequency of Siren is 988Hz
 
ThePhysicsXV said:
So what's the correct formula?
You are the student, so you must tell us that. :smile:
 
ThePhysicsXV said:
Frequency of Siren is 988Hz
That does not fully answer my question. That is the frequency that is heard how? When the car is approaching, or when it is stopped and you are stopped. Please post the full text of the question.
 
Forget this question, can you please delete this thread?
 
ThePhysicsXV said:
Forget this question, can you please delete this thread?
No, we don't delete threads with replies here. Please show more effort in your future schoolwork threads here. That's in our rules. I'll cut you a break on this thread.
 

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