Science Buddies: "Ask an Expert"

I’m helping my son with measuring the frequency on an acoustic guitar. We’re not sure how to measure the strings between the frets. Can you explain please?
He counted 20 frets but the project references 12. He said some guitars have more frets. Do we measure all 20 or just start at the neck and measure 12?

Hello,

I’m assuming that you are working on the project described here:

https://www.sciencebuddies.org/science- ... ency-speed

The string length that determines frequency is the distance from the saddle to the fret (or from saddle to nut for an open string). Thus for this experiment, you only need to measure the lengths of the strings from the saddle to each fret (and to the nut).

A short description of how to measure the lengths is given in step 2 of the experimental procedure. Please note that the saddle is angled so that the point at which the thickest string (bass) crosses is farther from the nut than the point where the thinnest (treble) string crosses. So you'll need to take your measurements from where each string crosses the saddle.

Your son is correct. Guitars have more that 12 frets and 20 or more frets is common. It's perfectly acceptable to complete the measurements for all the frets on your guitar. But you'll be able to make some interesting observations about string length, frequency and wave speed if you make the measurements for 12 frets.

I hope this helps. Please ask again if you have more questions.

A. Norman