🚀 go-pugleaf

On Thu, 30 Mar 1995, Cherie Lehman wrote:

> Steve and Donald mentioned that the pickle glowed nearer one electrode
> than the other and that it was not always the same side...

> Donald, I have had students eat the burned/cooked pickle, but it smells
> pretty bad and looks bad too -- even after just one run.  Low fat,
> turkey franks are a different matter though -- best when cooked in
> parallel.
>
> Bon appetite!

I haven't had students eat the pickles, but several of us on the faculty
have. In a private exchange about the safety of this, I was led to wonder
whether any chemistry between the metal electrodes and the pickle brine
could cause production of metallic compounds there which wouldn't be too
tasty. (I was never any good at chemistry, hating it as much as our
students hate physics.) I have no concern about the 'cooked' part of the
pickle. Nor have I ever had any offensive smells, using Warsaw Falcon
brand Polish Gherkins. But the I do not beat the poor pickle to death. I
show the effect, get the data efficiently and quickly, and the whole demo
probably lasts no more than 3 to 5 minutes.

In fact, I don't do the demo for classes (just privately, for fun) because
I firmly hold that one should not spend class time on demos which one
can't *fully* explain.  Demos should also only be used to make, illustrate
or reinforce important points in the context of the course. This demo
fails on both counts.

Another demo which fails on both counts is the smoke vortex generator. It
raises questions few of us are prepared to answer: "Why is the vortex so
stable?" (This requires *far* more mathematics than appropriate for this
course.) How can the vortex move so fast through the air? (Try to shoot
cotton balls or leaves that fast.) Why the particular rotation within the
vortex? (That one can be easily answered.) What is the significance of
this, or the relation to other physics we've learned, or will learn later?
What's the history of it? (Physicists once modeled elementary particles as
vortices in the ether--see Martin Gardner's book "The New Ambidextrous
Universe". Huge vortex cannon generators were used in Europe to fire large
smoke rings into the sky to ward off Thunderstorms and hail, in an attempt
to protect the vineyards. If you are not prepared to discuss these things,
or judge them peripheral to your course objectives, don't waste time doing
the demo. The precious time would be better spent on other things.

With any demo, ask yourselves whether this is being done for its physics,
or *merely* for its gee-whiz entertainment value. Much of what I see at
demo shows is in the latter category.

I appreciate the culinary advice that parallel-cooked franks taste better
than series-cooked ones. I never liked *turkey* franks any way they were
cooked. I have noticed a law of nature. If a food product has any of the
words 'light', 'lite', 'healthy', or 'nature(s)' in the name or on the
label, it will probably taste terrible, or have no taste at all. There
was a Garfield cartoon strip once in which Jon wondered why they don't
have a measurement for food taste. Garfield thought "They do; it's called
the calorie." I say, "Stick to the basic food groups: sugar, fat, salt and
chocolate." Whenever I hear the word 'wellness' bandied about it makes me
sick.

        -- Donald