Re: Sodaplay: Tacoma Narrows resonator

[Leigh Palmer <palmer@SFU.CA>]

> Or must a "resonance" always involve two separate oscillators, such as the
> typical coupled-pendulums lecture demonstration?

A resonance is seen when a system is excited by a variable frequency
oscillator (VFO - a periodic driven source of forcing function) and
the response of the system goes through an extreme value as some
resonant frequency is passed through by the oscillator. In the case
of nuclear magnetic resonance as done by, I think, Pound (even
chance), the oscillator itself is loaded by the system, and the
oscillator output is monitored to detect the resonance. In this
latter variant the oscillator is called a "marginal oscillator".
My meaning for the term "oscillator" is that of an active source of
periodic forcing function, not a passive system such as a pendulum.
I know that it is common to call such a system a simple harmonic
oscillator, but I feel those modifying words should always be used
when this sense of "oscillator" is intended. A function generator is
an oscillator, the thing I called a VFO in an earlier posting.

Leigh