Re: Konstantin Tsiolokvsky was wrong?!


Spaceman wrote:
"The Ghost In The Machine" <ewill@xxxxxxxxxxxxxxxxxxxxxxx> wrote in message
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In sci.physics, Spaceman
<Realspace@xxxxxxxxxxx>
wrote
So if e = 500 meters per second exhaust speed
The rockets will be crazy fast and will go much
faster than 500 meters per second.
(care to put that e into place and come up with rocket speed?)
:)

I get about 1150 m/s, given a 10:1 fuel/rocket ratio. Is
there a problem here?

So you say, that a 500 meter per second exhaust speed
would produce a 1150 meter per second rocket speed
in outerspace, as long as the fuel had 10 times more total
mass than the rocket?
I do think there is a problem there.
:)

I haven't been following all these follow-ups, but FWIW I get the
maximum (final) speed of the rocket to be e * Log(1 + m1 / m2), where
m1 is the initial mass of fuel, and m2 is the mass of the rest of the
rocket. So a 10:1 ratio of fuel to rest of rocket, with e = 500, would
give a final speed of 1199 m/s, while a 9:1 ratio (possibly what was
meant) would give a final speed of 1151 m/s.

.

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