Re: simplier is mor difficult

[Leigh Palmer <palmer@sfu.ca>]

> The original problem that I posted concerned a bar magnet allowed to fall
> vertically through a solenoid and continue falling a short distance after
> emerging from the bottom. Graph the voltage induced in the coil vs the
> time of fall.
>
> Since posting the problem, I have been hunting through my files for the
> oscilloscope displays that my students photographed.  No luck yet but I'm
> still trying to find them.
>
> As I remember it, the graph started from zero, showed a positive
> acceleration curve until the falling magnet reached a point near the
> center of the of the coil.
> Then there was a sudden drop of the graph line to a negative point far
> below the x axis.  The last portion of the graph was an  upward curve
> approaching the the x axis, as the induced voltage approached zero.

If the bar magnet was short with respect to the solenoid you had to
have a long, level part in the center where the magnet was far from
the ends of the solenoid. Is it possible that your shortness
condition was not met in your experiment?

Leigh