How to Calculate Error on Beat Frequency?

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To calculate the error on a beat frequency, it's essential to understand that the beat frequency is the difference between two frequencies. For example, if two tones at 1000 Hz and 1100 Hz are mixed, the beat frequency is determined by subtracting the lower frequency from the higher one. The accuracy of the frequencies affects the beat frequency's error range; if both frequencies have an error of ±10 Hz, the beat frequency could vary between 80 Hz and 120 Hz, resulting in an error of ±20 Hz. Using a differential equation is unnecessary for such straightforward calculations, which are best approached with basic arithmetic. Accurate error calculation relies on knowing the frequencies and their respective uncertainties.
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I'm being asked to calculate the error on a beat frequency. The beat frequency was found to be 1/20.0s



The equation given is
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The thing is I am not really sure where to go from there or how to get the derivative of that, any help or pointing me in the right direction would be much appreciated.
 
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Welcome to PF, Belgin.

You can only use that formula if you have the formula for f as a function of T and the error in T. It actually doesn't look like the right formula to me.

The beat frequency is the difference between two frequencies. Say you have two tones at 1000 Hz and 1100 Hz mixing together in your ear. You will hear 1000, 1100, the "beat" or difference between them and perhaps the sum. You would do 1100 - 1000 = 100 to calculate the beat frequency. If the accuracy on the 1100 and the 1000 is ± 10 Hz, then the beat could be anywhere from
(1100 - 10) - (1000 + 10) = 80 Hz to (1100+10) - (1000 - 10) = 120 Hz
so you would say it is 100 ± 20 Hz. I don't think it makes sense to use the differential equation in such a simple case - save it for a situation where you have multiplying at least.
 
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