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Re: [Phys-L] weightlessness



Unfortunately g is whatever the author of the text or paper says it is. We
have no language police to determine whether it is being used "correctly".
So the all cases is only for those cases where the author has agreed to use
that particular definition. Many authors do not agree.

John M. Clement
Houston, TX


On 06/27/2012 11:22 AM, Hugh Haskell wrote:
g is *not* zero at the space station. It's at least 8-9 N/kg. You
want to consider it somewhere where g is close to zero--perhaps in
deep space, where g might approach zero (but we all no that there is
nowhere where Newtonian gravity is exactly zero. If there were there
would be no galaxies or clusters of galaxies, or even superclusters
of galaxies).

Gaaack!

In all cases, g is frame-dependent. This is required by Einstein's
principle of equivalence.

a) In the frame of the space station, g *is* zero.

b) In the frame of the earth, g in the vicinity of the space station
is on the order of 9.8 m/s/s.

Talking about "the" g field without specifying which frame is being
used is ill-posed.

Contradicting one ill-posed statement and replacing it with another is
not an improvement.
http://www.av8n.com/physics/weight.htm
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