Re: Tuning Forks

[S Goelzer <s.goelzer@ATTBI.COM>]

Maybe you have already tried this, but I learned much by watching a
tuning fork illuminated by a strobe light.

HTH
Scott

On Friday, April 11, 2003, at 11:51 AM, Roger Haar wrote:

> Hi,
>
>         Here at the U of Arizona, in our junior-senior
> lab, we have the students make tuning forks as an
> introduction to machining metal.  We measure the
> fork's frequency when it is complete, with an
> amplified microphone and a frequency counter. This
> is quite popular activity.
>
>         But there are several questions about tuning
> forks that come up:
>
> 1. Physically,  how is the tuning fork bending in
> its fundamental and harmonics?
>
> 2.  What is the theoretical resonant frequency or
> how to design a tuning fork for a desired
> frequency?
>
> 3.   Many of our tuning forks including several
> commercially made tuning forks resonate   on 5th
> (or maybe 4th) harmonic.  Often this harmonic is
> much stronger than the fundamental, but usually
> this harmonic decays faster than the fundamental
> so we can eventually get a good measurement.
>         Is there a method of exciting a tuning fork to
> avoid harmonics?
>
> Thanks
> Roger Haar
*******************************************
Scott Goelzer
Physics Teacher
Coe-Brown Northwood Academy
Northwood NH 03261
sgoelzer@coebrownacademy.com
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