 |
 |
||||
|
|
||||
-Z- (z@gundam.com)
Wed, 8 Nov 2000 19:08:31 -0800
> -----Original Message-----
> From: owner-gundam@1u.aeug.org [mailto:owner-gundam@1u.aeug.org]On
> Behalf Of Mark Wilson
> Sent: Wednesday, November 08, 2000 00:00
> To: gundam@aeug.org
> Subject: RE: [gundam] Gravity within a colony (was: Funnels and flying
> MS)
>
> Uhm, if you don't understand the physics, then maybe you should look this
> up. There is no gravity generated by merely spinning a body. Gravity
> refers to a specific type of force; a "gravity gradient can only truly
> occur when there is really gravity present.
If I were talking about tides or actual gravity, you'd have a point here. I'm
not, and never have, spoken of gravity in a free-falling body, spinning or
otherwise. What I've spoken about is the gravity-like accelerations and the
pseudogravity felt by occupants of such bodies. A gravity gradient can occur
any time there's a differential in acceleration across the length, width or
breadth of an object in motion. That's why they call the anti-acceleration
devices worn by fighter pilots "g-suits" -- they compensate for the gravity
gradient created by changes in acceleration of high-speed aircraft.
> Centripedal acceleration is not angular acceleration. Even if the rotation
> rate is constant, there is centripedal acceleration (think about his--even
> when the merry-go-round isn't accelerating, you still have to hold on to
> avoid being flung off).
If you're going to insist on using a term rigorously, you might try spelling it
correctly. It's "centripetal" force, which is the force necessary to keep an
object moving in a circular path and that is directedinward toward the center of
rotation.
"Centrifugal" force, on the other hand, is the force that tends to impel a thing
or parts of a thing outward from the center of rotation. With regard to this
discussion, it's the force that an object moving along a circular path exerts on
the body constraining the object and that acts outwardly away from the center of
rotation.
> > The basic equation for describing the magnitude if the force is f=mv^2r,
> where f
> > us the Coriolis force, m is the mass, v^2 the angular velocity in degrees
> per
> > second and r the radius in feet (not meters) of the rotating module.
>
> The dimensions for force are mass*length/(time^2). Degrees are not units
> you can multiply by without conversions. Your equation above gives:
> f=mv^2r. According to you, the dimensions for force are
> mass*(length/time)^2*deg/s.
>
> With all due respect, I think I'll go with Isaac Newton's version, not
> yours.
With all due respect, sir, it's Newton's version -- not your interpretation --
on which all of the figures I've cited are based.
> Also, the "Coriolis" effect is measured tangential to the circle, not
> perpendicular. We are interested in the forces perpendicular to the circle
> edge.
Ah, I think I see where you're going wrong here. Quoting the NASA design study
here: "The direction of the [Coriolis] force is perpendicular to both the
velocity and the axis of rotation." And later: "Earth based experiments are
not a good approximation of rotational effects in space because most tests
conducted on Earth orient the long axis of the body parallel to the axis of
rotation. In space these axes would be mutually perpendicular."
> Look, you really don't seem to have a grasp on the physics here. Quoting a
> study doesn't really matter if you don't understand the basics.
If agreement with you in this regard is the measure of my understanding, then
I'll never have a grasp of the physics here. But I should point out that, to
date, you're a minority of one and your derivations do not conform to those of
anyone else on this list who've put pencil to paper (or figners to keypad) to
work this things out.
> These numbers again are way too high.
Sez you. Do I hear a second? Does anyone else see any merit in his numbers
versus mine?
> I would NEVER tell you how to turn a wrench on a system I didn't design;
> please leave the physics to those who understand it. There is way too much
> pseudo-science on this group to begin with.
You're polite about it, but you're by far the most insulting little sniper I've
ever had the misfortune to encounter in cyberspace. A word of advice: it's not
a good idea to antagonize people you don't know, especially those with 20 years
of military service dating back to Vietnam. If you ever make a pronouncement
like this to my face, I'll demonstrate f=mv^2 for you in a manner that you'll
find equally unpleasant. (Hint: human bone breaks under a pressure of eight
pounds per square inch or 0.562456 kilograms per square centimeter.)
But I'm a fair man. Since you're obviously better qualified than I in these
matters, I'll leave the job of scientific explanations entirely up to you. No
more misleading the gullible for me; I'll defer to your expert opinion and maybe
even learn a thing or two. Enough pseudo-science from a guy whose name we can't
spell! Now we have Mark Wilson to enlighten us, so it's time for -Z- to retire
and leave the physics to someone who understands it.
I look forward to seeing your Gundam Physics page on the Web, explaining
correctly all of the things I got wrong and giving the actual figures for all of
the items of interest to the GML readership -- transit times in space, weather
patterns in a space colony, construction materials and methods, power sources
and energy yields, the dynamics of colony drops, and all that jazz. As soon as
it's up, I'll take all that crap off my page and put in a link to yours.
(*sigh*) Well, it was nice while it lasted, but now that I've been exposed for
the fraud that I am, I guess I'll have to find another list, where I can
continue to fool the ignorant and pretend that I really know something.
This will certainly be the last I say to you, on any subject you care to name.
-Z-
-
Gundam Mailing List Archives are available at http://gundam.aeug.org/
This archive was generated by hypermail 2.0b3 on Thu Nov 09 2000 - 11:54:07 JST