Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: possible stiffness effect



John Denker wrote:

Is the 12% difference due to stiffness or to something else?

1) A sensitive check would be to look at the spectrum. That is,
plot the frequency of the Nth standing wave as a function of N.
In the absence of stiffness, you expect the simple Pythagorean
integer ratios. Stiffness will cause "stretched" intervals.

Very clever. For a standing wave with two-loops we had
f=1.66 Hz while for the wave with three loops f was close
to 2.50 Hz. This would indicate no stiffness effect. Perhaps
I will find a student willing to take this as a project. Will
share more information, if any.

It would be useful to know if the "standard model" (n lumped
masses and n-1 massless springs ) can be used to predict how
v depends on f, once ST has been determined experimentally
for a given tension T. Or at least what should the ratios of
frequencies be for n=2,3,4 and 5 when everything else (mass,
length, geomety, material, tension, k per unit length, and ST)
is known about the spring.
Ludwik Kowalski