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Re: little gee -- ho hum


Little g(x) most certainly is an acceleration, at each and every point (x).
Loudly asserting that it is not won't change anything.

Anybody who disagrees is requested to provide some theoretical and/or
experimental methods for disproving the assertion that g(x) is an
acceleration.

John Denker is absolutely correct: As he sits at his computer and muses, he
also measures the value of the local gravitational constant to be 9.8m/s/s
-- His measurement consists in determining his increasing rate of fall
toward the center of the Earth as he sits at his computer. "See", he says,
"g=a, therefore g is acceleration"

Let's all gleefully do this. The value of g=~9.8m/s/s at out computers,
therefore we all must be accelerating toward the center of the Earth --
computer, chair, and body together. Everybody say "Wheee".

Look folks, we have this same discussion from time to time in another guise:

SumF=ma -- Now the net force is usually EQUAL to the mass times the
acceleration of the body, but the net force is neither mass nor
acceleration!!! Here is one example: the net force is mg and that force is
equal to the acceleration of the body x its mass: force == mg = ma. See
that!! The g is on the LHS and the a is on the RHS -- Force is on the LHS
and motion is on the RHS!!! They are NOT the same thing!

Unless of course one is teaching some sort of convoluted super hyperbolic
string theory to one's intro class.

In this one very narrow and very specific case g is numerically equal to a,
but g is not acceleration. And saying so will likely confuse the
beejeebers out of students -- out of instructors as well, it would seem.

What amazes me is that we have to have this discussion -- Isn't this
obvious!!! And I am absolutely flabbergasted to see John Denker with
contrary views -- I conclude that he is just joshing us -- John please tell
us that you are kidding -- that you haven't lost your intellect!


Jim Green
mailto:JMGreen@sisna.com
http://users.sisna.com/jmgreen