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Question involving beats and sound waves

Hi, I have a question involving beats and sound waves.
When two sound waves (one with a MUCH LARGER Frequency than the other) combine, what would happen? Would there still be a beat pattern? Me, I think that if there still is a beat pattern, it would have the same frequency as that of the highest frequency of one of the combining waves. Am I right, or horribly wrong? I'm really puzzled by this. Thank you very much for your time.
 

Answers and Replies

Tom Mattson
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insertnamehere said:
Me, I think that if there still is a beat pattern, it would have the same frequency as that of the highest frequency of one of the combining waves. Am I right, or horribly wrong?
Check your book and find the formula for the beat frequency. It is not the higher of the two combining frequencies.
 
jtbell
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If wave #1 has a much larger frequency than wave #2, then what you get is (approximately) a wave of frequency #1 whose amplitude varies according to frequency #2. This is the principle used in AM (amplitude modulation) radio signals.
 
quasar987
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IMO, the answer can be seen clearly by looking at the "unmanipulated" equation of "beats", i.e. the simple addition of the two waves:

[tex]y(t) = Acos(\omega_1t) + Acos(\omega_2t)[/tex]

what does the addition of these two graph looks like if [itex]\omega_1 << \omega_2[/itex]?
 

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