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Re: toroidal perpetual motion machine



At 08:53 6/28/00 -0400, John D wrote:
...the length of the meniscus on the outside of the toroid is longer
than the length of the meniscus on the inside. But the height of the
meniscus is the same everywhere, to a more-than-sufficient
approximation. So there's more total force on the outside.

....
It appears that some energy (force times distance) was imparted to the tube
when it rotated, but this energy did not come from the water in any obvious
way, because the water is in the same state before and after the rotation.

That's impossible. The foregoing analysis must be wrong (or at best
incomplete). So what is really going on here?....

Acknowledgement: I got this from Richard Feynman, and I believe it was
original with him.



Hmmmm... my evil twin brother is insisting that he...well we...
put this one to the test appropriately.

He whispers, "Feynmann was a well known magician - he could
open secure safes after he had sandpapered his finger tips and
obtained a stethoscope, could he not? "
I respond that everyone is acquainted with the source of his
safecracking power, despite his misdirection. After chiding him
for his lack of charity, I add,
"So what is Feynmann's misdirection, this time?"

"It's obvious that any self-respecting physicist sees tires and
inner tubes as somewhat mysterious - so that's a natural route
for a sleight of hand concerning surface tension and capillarity."

"Alright, Evil One," I reply, what WOULD physicists feel
comfortable with as an example of capillarity?"

E.O immediately expletes, "How about capillary tubes?"

Now this does indeed seem reasonable to me, so I remark,
"You must be recalling that a narrow glass tube allows the interior
water level to rise above the outside meniscus."

"Listen to me" Evil One continues, "Don't call it a capillary -
think of it as made with perfectly transparent flexible rubber,
like a long thin inner tube."

"Yes..."

"Well, it stands to reason. If the inner capillary head did not
balance the longer outside meniscus, the torus shape would rotate,
like a snake trying to shrug off its skin, wouldn't it?"

"And it doesn't does it?"

"Well, no, I guesss not."

"Q.E.D"

Now I have to apologize for my Brother, the Evil One.
He's always nit-picking. He didn't prove a thing.

It avails not to tell him that Leonardo, Newton, Maxwell, Laplace,
Young, Rayleigh, Gauss, Poisson and Van der Waals covered most
surface tensile cases of interest, and developed some math models
of more than passing value.

I say, if you can't exhibit a differential equation on topic,
do you really understand it?



brian whatcott <inet@intellisys.net>
Altus OK