How Does the Doppler Effect Alter the Sound of a Horn from a Moving Truck?

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The discussion centers on understanding how the Doppler Effect alters the sound frequency of a truck's horn as it moves away from an observer. A truck traveling at 70.0 kph emits a horn sound at 400 Hz, and the air temperature is 25 degrees Celsius. Participants suggest starting with the Doppler shift equation to identify known and unknown variables. There is a struggle with applying the equations, indicating a need for clearer understanding of the physics involved. The conversation emphasizes the importance of breaking down the problem to solve for the altered frequency.
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Homework Statement


A truck is traveling 70.0 kph away from you. The Driver is blowing a horn with a frequency of 400 Hz, air temperature is 25 degrees celcius.:rolleyes:


Homework Equations



doppler effect


The Attempt at a Solution


none
 
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Moroni said:

The Attempt at a Solution


none

This makes it hard to want to help.

I would suggest you start with the Doppler shift equation and classify the variables involved by unknown and known, then you can think about the physics if you have more unknowns than you can solve for mathematically.
 
Sorry I should clarify. I said none because I can't even figure out how to use the equations I've been given.
 
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