Max & Min Frequencies from Tuning Fork Revolution

AI Thread Summary
The discussion revolves around calculating the maximum and minimum frequencies heard by a second person when a tuning fork with a frequency of 512 Hz is swung in a circle. The key concept is the Doppler Effect, which explains how the frequency changes based on the relative motion between the source and the observer. Participants emphasize that the position of the observer is irrelevant, as the tuning fork will approach and recede from them during its rotation. The problem-solving approach involves determining the points in the rotation that correspond to the highest and lowest frequencies. Understanding the Doppler Effect is crucial for solving this physics problem effectively.
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Homework Statement



A tunning fork with frequency f = 512 Hz is held by someone who swings it vigurously in a circle in the horizontal plane. The radius of the circle is 1.0 m, and the frequency of revolution is 3.0 rev/s. (a) What are the max and the min frequencies that a second person would hear? (b) What part of the rotation corresponds to the highest frequency the second person hears, and which part corresponds to the lowest?

Homework Equations



1 rev/s = 60 rpm

1 RPM = 0.01666666667 Hz

w = 2*pi*f

The Attempt at a Solution



I have no idea how to treat this problem! I mean I cannot get the idea for relating this problem with waves and sound equations! Can you help me? Thanx
 
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You should familiarize yourself with the Doppler Effect and related equations before re-attempting this problem.
 
Have you studied the doppler effect?

I think this question is in a funny order, wouldn't you first find the points of max/min shift then find what the shift is there?
 
lewando said:
You should familiarize yourself with the Doppler Effect and related equations before re-attempting this problem.

Disconnected said:
Have you studied the doppler effect?

I think this question is in a funny order, wouldn't you first find the points of max/min shift then find what the shift is there?

Hi guys thank you for the hint!

I already solved the problem with Doppler effect eq. but I still cannot get where is the second person. I mean is he at 1m away from the one who is holding the fork?

Thank you so much
 
It doesn't matter where he is. No matter where he happens to be, the tuning fork will always be moving directly towards him at some point in its revolution, and directly away from him at some other point.
 
ideasrule said:
It doesn't matter where he is. No matter where he happens to be, the tuning fork will always be moving directly towards him at some point in its revolution, and directly away from him at some other point.

Yes you're right!

Thank you so much!
 
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