Mike Monett wrote:
"Tom Donaly" wrote:

[...]

Most undergraduate physics texts have, or should have, discussions
of vibrating strings. There's a good treatment of the subject in
William C. Elmore's and Mark A. Heald's book _Physics of Waves_
published by Dover.

If you wanted to get in an argument you could say that the energy
on both sides of the node isn't traveling, but is merely
alternating between potential and kinetic.

Yes, I thought about that a bit before posting. It seems logical a
plucked string sends a wave in both directions, where it is
reflected and returns to create a standing wave.

When it forms a standing wave, it seems reasonable to say the energy
is alternating between potential and kinetic. But isn't that similar
to what happens on a transmission line that is exactly some multiple
of a quarter wavelength long?

Such strings have loss (or you wouldn't be able to hear them).

Loss is a taboo subject on this newsgroup because it makes wave
behavior too hard to understand for the savants posting here.

73,
Tom Donaly, KA6RUH

Regards,

Mike Monett

When you pluck a string, you are exciting the whole string at once.
If a sound wave of the right frequency impinges on a string
perpendicular to the string's axis, the string will vibrate
sympathetically. In that case, it's hard to justify saying that two
waves are traveling in opposite directions up and down the string.
Nevertheless, the solution of the partial differential equation
describing the motion of the string, as proposed and solved by
the French mathematician D'Alembert, in 1747, is consistent with the
idea of two waves of arbitrary function traveling in opposite directions
on the string. If I were you, I'd find a copy of the differential
equation of a wave on a string and compare it to the same equation
describing an electromagnetic wave on a transmission line. How similar
are the two?
73,
Tom Donaly, KA6RUH