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In lugnet.space, Jason J. Railton writes:
> In lugnet.space, Jesse Alan Long writes:
> > I knew that an airplane wing will continue to fly, even if
> > it was inverted but that is because, I believe, unless otherwise corrected,
> > that the plane has a curved surface and as long as it has the curved
> > surface, then no matter how you fly, you still receive lift from the air and
> > a downward force but the lift is stronger than the downward force because
> > more air goes down than it does going up on the airplane but it is not of
> > such an unbalanced ratio that it can not fly down to Earth because that
> > would violate the laws of gravity.
>
> Well, it's more about the angle the wing is inclined to the airflow. Just
> keep it tilted upward to the air flowing past you, keep your speed up, and
> you should get some lift. Newton says you're deflecting air downwards.
> Aerodynamics says a lot more but it's much harder to follow.
>
> > I always thought that heat was able to boil liquids into gas but why does
> > heat not present a role into outer space? Why would pressure matter in
> > outer space?
>
> The boiling point of a liquid depends on the pressure of the environment
> it's in. Under high pressure, like in a pressure cooker, water boils at a
> higher temperature (that's the point of the cooker). Under low pressure, it
> boils at a much lower temperature. High on a mountain, in thin air, it
> takes a lot longer than 3 1/2 minutes to boil an egg, because the water
> boils below 100°. In space, with zero pressure, liquids boil instantly.
> Inside a pressurised space capsule, water sticks together in floating
> bubbles - but outside, the molecules would just disperse. [There are
> rumours of water droplets on surfaces in a depressurised section of Mir
> following an accident, but these have yet to be confirmed or explained].
>
> I wouldn't try tis with other liquids in your space capsule - water
> molecules have a little stickiness (which gives us surface tension - how
> insects can stand on the surface of water). It's possible to break this
> down by adding detergents - so soapy water would probably go everywhere.
>
> > I always thought that you could make a plasma powered space
> > craft in a similar manner as you would build a welding torch so please
> > explain to me why the plasma engine would present a terrible idea for my
> > space craft? I mean, I know that plasma, in a uncontrolled state, can
> > present a great danger but what about a controlled plasma environment, if
> > any such environment is possible on a space craft?
>
> Well, conventional propulsion is all about reaction thrust. You blow some
> mass backwards, and you get a reaction pushing your mass forward. Jets,
> rockets and propellors all use this trick. The difference with rockets is
> they don't take anything in from the atmosphere. Propellors and jet engines
> use air as their propellant. A rocket, and the combustion chamber inside a
> jet engine, both use a chemical reaction (burning) to generate gas at a high
> temperature. This causes rapid expansion, and the only vent for this is
> rearwards. In a jet engine, it also heats the air, and that expands and
> blows backward too. A propellor just pushes air (or water) backwards.
>
> My knowledge of plasma is limited, but I guess it would be an extreme
> example of the super-heated expanded gas. I believe it can be guided by
> electro-magnetic fields, so maybe you could accelerate it even more with
> such fields.
>
> > The final question I have to ask is could it be possible, either in a
> > science fiction realm or a realistic realm for a Harrier type space craft to
> > actually fly into outer space? I thank you for clearing the confusion in my
> > mind, Jason.
>
> Yes - if you had enough thrust you could go straight up - but you'd need to
> keep the thrust on just to hover against the force of gravity. All our
> spacecraft (Apollo, Shuttle, French and Russian satellite launchers) start
> off going straight up, but soon tilt over into orbit. To get away from
> Earth, they accelerate around and around, getting into higher and higher
> orbits, until they're going fast enough to fly off ('escape velocity') -
> though they still fly off in an arc, not in a straight line away from Earth.
>
> It would take too much fuel for NASA to send a rocket straight up, but it
> might be possible one day. Anti-gravity devices would help.
>
> Jason J Railton
You said in the last letter before this letter that some liquids (referring
to the reaction to friction of certain particles in outer space) are
viscious while some solids are very hard and smooth in reaction to friction
in outer space. If liquids boil in outer space, how is this possible in
outer space? Do you really mean that gases, not liquids, are very viscious
with the concept of friction in outer space?
I also must say that if the rumors (forgive my American dialect of the
English language) are true about Mir and the condensation of water droplets
on one of the observation windows, then the whole concept of boiling liquids
in different environments would be held in serious jeopardy and we may have
to reorganize our thoughts on condensation, the boiling points of liquids,
and air pressure in outer space and on our planet.
I do not understand why you say that it would be considered a terrible idea
for me to use plasma as a heated engine and yet you say that it could be
guided with electromagnetic fields. Would these electromagnetic fields not
only stabilize the plasma but also make the plasma increase in speed as
thrust or would the electromagnetic fields only provide a stable environment
for the plasma or would neither of these possibilities be true for my space
craft?
I have two more questions to ask you, Jason. The first question is would
Newtonian physics contradict or complement the laws of aerodynamics? If
there are any contradictions or further explanations from these rules,
please explain them to me, Jason. The second question is what would work
for an antigravity device for space craft, that is what materials and
options could we use for space craft? I am glad that the long ordeal about
the eternal space craft ethical war is almost over in Lugnet.
Jesse Long
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Message has 2 Replies:
 | | Re: Couldn't resist
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| (...) Laws of aerodynamics (aero*dynamics*) are nothing but Newtonian physics. The whole governing equation of aerodynamics, the famous Navier-Stokes equation, is just a different representation of our well known F=ma. By the way, is it a miracle (...) (23 years ago, 4-Aug-00, to lugnet.space, lugnet.off-topic.geek)
| | | Re: Couldn't resist
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| (...) I didn't necessarily mean in space. I was just talking about liquids in general (on Earth, in an atmosphere). Clearly if you're trying to push your way through something, a gas is easier than a liquid, which is easier than a solid. But, this (...) (23 years ago, 2-Jul-01, to lugnet.space, lugnet.off-topic.geek)
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Message is in Reply To:
| | Re: Couldn't resist
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| (...) Well, it's more about the angle the wing is inclined to the airflow. Just keep it tilted upward to the air flowing past you, keep your speed up, and you should get some lift. Newton says you're deflecting air downwards. Aerodynamics says a lot (...) (23 years ago, 29-Jun-01, to lugnet.space, lugnet.off-topic.geek)
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