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Re: charge-distribution misconception

At 08:55 AM 2/6/01 -0500, Ludwik Kowalski wrote:

If this misconception is common, as it was in my case, then it is fair
to ask about its origin. We can certainly not blame Aristotle for it. Neither
it comes to us with everyday language. Why is it so common?

Just a guess: Perhaps it is an example of the well-known "negative
transference" phenomenon. In this case that means remembering the answer
to one problem and mis-applying it to mis-answer a different problem. In
particular I have in mind the pair of questions being
a) Where does the corona current come from? ... in which case the
answer is that all the current comes from the sharp point, and is a very
strong winner-take-all function.
b) Where does the charge sit? ... in which case the answer is that it
is distributed according to capacitance, which goes like radius for two
widely-separated spheres, and is an even less-strong function for closer
spheres, as discussed in my previous note.

Other examples of negative transference that spring to mind include:
-- If you know how to drive a car and want to learn to fly an airplane,
you are virtually guaranteed to have misconceptions about how the
airplane's steering works, how the throttle affects speed, and about ten
other things. Unlearning these things is a burden.
-- Cross-country skiing technique is just enough different from downhill
skiing technique that there is some negative transference. (Of course
there are helpful similarities leading to positive transference, too.)