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How do beats help determine whether two sound waves are of the same frequency?

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Answer
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Hint : The beat is the phenomenon that occurs when two waves meet while traveling along with the same medium. The interference of waves causes the medium to take on a shape that results from the net effect of the two individual waves upon the particles of the medium.

Complete Step by step explanation:
Step 1: if two upward displaced pulses having the same shape meet up with one another while traveling in opposite directions along with a medium, the medium will take on the shape of an upward displaced pulse with twice the amplitude of the two interfering pulses. This type of interference is known as constructive interference.
Step 2: If an upward displaced pulse and a downward displaced pulse having the same shape meet up with one another while traveling in opposite directions along with a medium, the two pulses will cancel each other's effect upon the displacement of the medium and the medium will assume the equilibrium position. This type of interference is known as destructive interference.
Step 3: Beats are the periodic and repeating fluctuations heard in the intensity of a sound when two sound waves of very similar frequencies interfere with one another. A beat pattern is characterized by a wave whose amplitude is changing at a regular rate. The beat pattern repeatedly oscillates from zero amplitude to large amplitude, back to zero amplitude throughout the pattern. Constructive interference results in a large amplitude and destructive interference results in zero amplitude. Therefore, when constructive interference occurs between two crests or two troughs, a loud sound is heard. This corresponds to a peak on the beat pattern. When destructive interference between a crest and a trough occurs, no sound is heard and this corresponds to a point of no displacement on the beat pattern.
Step 4: therefore, we can say that the beats pattern occurs when two waves of similar but not identical frequencies are superimposed.

Note: The wave resulting from the superposition of two similar-frequency waves has a frequency that is the average of the two. This wave fluctuates in amplitude, or beats, with a frequency, called the beat frequency. We can determine the beat frequency by adding two waves together mathematically.