Re: A weighty subject

[Bob Sciamanda <trebor@VELOCITY.NET>]

> "What else is there to say?"

This is excellent as far as it goes, but what else there is to say are
things like: "What is the weight of an astronaut in orbit, etc. " (I
refuse to say he is "weightless")  H,R&W define "weight" only for the
pedestrian surface bound earthling!

Bob

Bob Sciamanda (W3NLV)
Physics, Edinboro Univ of PA (em)
trebor@velocity.net
http://www.velocity.net/~trebor

----- Original Message -----
From: paul o johnson <pojhome@FLASH.NET>
To: <PHYS-L@lists.nau.edu>
Sent: Friday, October 15, 1999 5:12 PM
Subject: Re: A weighty subject


> . . .
> Can we not
> agree on the very lucid and reasonable distinction in Resnick, Halliday,
> Walker, 5th ed., p. 326, viz,
> <p>"The gravitational acceleration <i>a sub g</i> computer from <i>F =
> GMm/r^2</i> is not the same as the free-fall acceleration <i>g</i> that
> we would measure for a falling object (and that we have approximated as
> 9.80 m/s^2 near Earth's surface)."
> <p>"The two accelerations differ for three reasons: (1) Earth is not
uniform,
> (2) it is not a perfect sphere, and (3) it rotates. Moreover, because
<i>g</i>
> differs from <i>a sub g</i>, the weight <i>mg</i> of the object differs
> from the gravitational force of the object for the same three reasons."
> <p>That makes sense to me. What else is there to say?
> <p>poj
> <br>&nbsp;</html>
>
> --Boundary_(ID_KHzZWFZrtcrt0iqqa8HVww)--