Orchid XP v8 wrote:
> The London Natural History Museum also has a full-size blue whale model. 
> And the lobby features a Diplodicus skeleton. 

Hmmm... I'm pretty sure I was there, along with the British museum. I 
don't remember the whale, so maybe not.

Also, New York has the only *actual* complete T-Rex skeleton. All the 
others are plaster casts.

-- 
Darren New / San Diego, CA, USA (PST)

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Darren New wrote:
> Orchid XP v8 wrote:
>> The London Natural History Museum also has a full-size blue whale 
>> model. And the lobby features a Diplodicus skeleton. 
> 
> Hmmm... I'm pretty sure I was there, along with the British museum. I 
> don't remember the whale, so maybe not.

The blue whale is in the mammals exhibit. If you didn't visit that 
particular gallery, you wouldn't have seen it. (Also, I'm not sure 
precisely how long it's been there, or when you visited.)

> Also, New York has the only *actual* complete T-Rex skeleton. All the 
> others are plaster casts.

The London museum has a few actual skeletons. Usually it's almost 
impossible to tell what the hell you're seeing. The bone casts that have 
been assembled into a life-like pose are much more interesting, 
visually. (Obviously to a scientist the real thing is far more important.)

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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> -----Original Message-----
> From: scott [mailto:sco### [at] scottcom]
> Earth is rotating.  If the Earth rotated at the right speed then there
> would
> essentially be no downwards force (at least on the equator) and
> everything
> would float.

Question:  Wouldn't it be more accurate to say that everything in
contact with the Earth's surface would float?

After all, after you lose contact with the Earth's surface, the Earth
should (theoretically) no longer be applying the centripetal force to
throw you out, meaning that Gravity would again take over.

The corollary to this is that rotating a space station for gravity only
works when you're standing on the floor; anytime you're floating in the
air, you can watch the whole station rotate past you as you just sit
there :)


...Ben Chambers
www.pacificwebguy.com

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>> Earth is rotating.  If the Earth rotated at the right speed then there
>> would
>> essentially be no downwards force (at least on the equator) and
>> everything
>> would float.
>
> Question:  Wouldn't it be more accurate to say that everything in
> contact with the Earth's surface would float?

No, even things in the air would appear to float because everything is going 
at the right speed to essentially "orbit" the Earth (ok a few m/s difference 
between 6400km and 6400.001km from the centre, but...).

Just like if you fire a rocket horizontally at the right speed (with no 
drag, eg on the moon) it will stay at exactly that height and orbit the 
moon.  Spinning the Earth fast enough would essentially make everything 
orbit the Earth around the equator, the force of gravity would be exactly 
right to keep everything floating at that speed.

But also the air would be floating now, so who knows what would happen to 
the atmosphere!

Oh and you might get a headache from the very fast day/night cycles ;-)

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Chambers wrote:
> The corollary to this is that rotating a space station for gravity only
> works when you're standing on the floor; anytime you're floating in the
> air, you can watch the whole station rotate past you as you just sit
> there :)

An interesting related aside: If you're in a rotating space station, it 
seems like the "gravity" would appear stronger or weaker depending on 
weather you were moving with or against the direction of rotation, so 
you should be able to, for example, jump further in one direction than 
another.

Assuming the radius is small enough for the effect to be obvious, that's 
got to feel really odd.

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Kevin Wampler wrote:
> Assuming the radius is small enough for the effect to be obvious, that's 
> got to feel really odd.

http://en.wikipedia.org/wiki/Coriolis_effect

-- 
Darren New / San Diego, CA, USA (PST)

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Darren New wrote:
> Kevin Wampler wrote:
>> Assuming the radius is small enough for the effect to be obvious, 
>> that's got to feel really odd.
> 
> http://en.wikipedia.org/wiki/Coriolis_effect
> 

I had thought that the Coriolis effect only dealt with the "force" 
resulting from an object changing it's distance form the axis of 
rotation.  Looking at the article, however, it appears that I was 
entirely incorrect and that the definition covers what I described as 
well.  Good to know!

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Darren New <dne### [at] sanrrcom> wrote:
> Invisible wrote:
> > Hmm. But is your planet rotating? Or is your planet actually stationary 
> > and the universe is rotating around it? ;-)

> The planet is rotating.
> http://en.wikipedia.org/wiki/Foucault_pendulum

  Some people actually have misconceptions related to this, or more precisely,
related to inertial coordinate systems. Some people think that basically any
coordinate system, even a rotating one, is inertial, and can be used as the
basis of any inertial calculations.

  Of course this is not so. A coordinate system which is not intertial is
an accelerating coordinate system, and a rotating coordinate system (such
as one fixed on Earth) is accelerating. The difference to a truely inertial
coordinate system is that this acceleration can be measured from within
the coordinate system itself. The focault pendulum is one example of how
this can be measured.

  These people often also have the misconception that it's not possible
to say if you are in a truely inertial coordinate system or not. But of
course this is not so, as it can be trivially measured: If there is no
any kind of acceleration you are in a truely inertial system.

  (If I'm not mistaken, the idea in general relativity that gravitation
is inertial movement and not an accelerating force, is related to this.)

-- 
                                                          - Warp

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> -----Original Message-----
> From: Invisible [mailto:voi### [at] devnull] 
> The way the Oak does it is quite ingenius: IT USES THE LAWS OF
PHYSICS.
> Specifically, as water evapourates out of th leaves, that sucks more
> water out of the branches - which sucks water out of the thunk, whic
> sucks water out of the ground. So it's a completely passive system,
and
> it always delivers exactly the right amount of water without needing
> any
> control systems.
> 
> Mankind, you have been PWN3D.

Rofl :)

...Ben Chambers
www.pacificwebguy.com

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