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Question
A source of sound with adjustable frequency produces 2 beats per second with a tuning fork when its frequency is either 476 Hz of 480 Hz. What is the frequency of the tuning fork?
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Solution
Given:
First Frequency \[f_1\] = 476 Hz
Second frequency \[f_2\] = 480 Hz
Number of beats produced per second by the tuning fork m = 2
As the tuning fork produces 2 beats, its frequency should be an average of two.
This is given by :
\[f = \frac{\left( f_1 + f_2 \right)}{2}\]
\[f = \frac{\left( 476 + 480 \right)}{2} = 478 \text { Hz }\]
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