# Fundamental Frequency and Musical Harmonics

1. May 24, 2005

Ok, I was given a question in homework and was never told the right answer.

If the Fundamental Frequency = 15Hz, the 3rd Harmonic = ?

I estimated it at 45Hz because of an example

The example was;

Harm 1 = 100 x 1 = 100Hz
Harm 2 = 100 x 2 = 200Hz
Harm 3 = 100 x 3 = 300Hz

If so, the third Harm is 3:1, Ergo, if Harm 1. WAS 15Hz, you'd use the 3:1 which was applied on the example and discover it was 45Hz.

Am I correct in saying this or is it something different?

2. May 24, 2005

### quasar987

It's good. The formula is

$$f_n=nf$$

where f_n is the n-th harmonic and f is the natural frequency, aka first harmonic.