A string has its 4th harmonic at 31.5 Hz. What is the fundamental frequency? Unit= Hz

Physics

1 answer:

kondaur [170]3 years ago

3 0

Answer:

7.9Hz

Explanation:

Step one:

given data

We are told that the fourth harmonic is at 31.5 Hz

We know that harmonics are a multiple of the fundamental frequency, such that if the fundamental frequency is 25Hz, then the second harmonic is

2nd= 2*25= 50Hz

3rd= 3*25= 75Hz........and so on

Step two:

In this problem, we are told that the 4th harmonic is 31.5Hz, that is

4th= 4*f= 31.5

Divide both sides by 4 to get f

f= 31.5/4

f= 7.9 Hz

Hence the first/fundamental frequency is 7.9Hz

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