Say you have a teleportation device. Basically, anything can pass through freely.

If you put one end at sea level, 100kPa.. how far up would you have to put the second in order for the air to escape the earths atmosphere permanently and dissipate into space?

I don't know much about vacuum physics and gravity and such. How would you figure such a thing out?

The edge of our atmosphere is 60 miles up IIRC

Difficult question, since you presumably don't want the released air to fall back to Earth.

You need to work out the average velocity of the gas particles in the air, which is perhaps a few hundred metres per second. Then, work out the height from which the Earth's escape velocity is a few hundred metres per second (from the surface it is 11 km/s). Something less than that height would be required, since the gas has a Maxwellian distribution of velocities.

That's very hypothetical, considering it would break the second law by making it easy to construct a perpetual motion machine. Unless it requires energy to teleport, simply by teleporting an object to a higher position you increase its potential energy for free :eek:

wouldn't the water vapor freeze and make a ice bubble around it with a internal pressure of 1 bar (space is cold).

Thanks for the responses guys. Glad to hear this really is a difficult.

Zephyr,
Assuming it didn't break the second law.. this teleportation thing was somehow magic, what would you expect to happen? Would the gas even escape into space or would it, as orcot suggests, freeze around the teleportation gate?

I wonder if such a thing could be modeled..

it seems to me that in order for it to work the atmosphere (air) must escape earths gravity.
so the minimum distance would be the moons surface

in my humblest and lay opinion

wouldn't the water vapor freeze and make a ice bubble around it with a internal pressure of 1 bar (space is cold).
Actually, since space is (largely) a vacuum it does not have a temperature.
edited for typo/srr