Re: Waves

[Leigh Palmer <palmer@SFU.CA>]

> >  The high pitched precursor
> > to the main pulse is likely due to the transmission of longitudinal
> > modes in the cable at speeds higher than those of the transverse mode.
>
> Yes, but why is "modes" in the plural for longitudinal? Would one expect
> the cable to transmit longitudinal waves with a range of speeds? Why?

Please excuse my sloppy terminology; there is only one longitudinal
mode, of course. The transmission of compressional waves in solids is
dispersive, but I don't think I can give a good answer to your "why"
question. The transmission of transverse waves in a stiff string is
also dispersive, by the way.

> Flagpoles are amusing too, and can get people quite annoyed, for some reason.

Hah! Annoyed? You should have seen the people on that stairway. I was
with a couple of colleagues who teach high school physics in New Jersey
and New York. They knew what I was doing, but fortunately for us the
rest of the people waiting in line on the stairs inside the Statue did
not know who was causing the disturbance. Perhaps your disturbance of
the flagpole and mine of the Statue of Liberty were considered to be
somehow unpatriotic.

Leigh