# Pressure in outer space

1. Apr 11, 2007

### nomorevishnu

Pressure in outer space!!

lets imagine a cube kept in the outer space....and lets take a small element inside the cube....with thickness dy and width dx...or the smalles volume elemnt inside the cube would be another cube right...and....it would be in equilibrium...so the pressure actin on that element from the top and the bottom are gonna be the same .....

think abt two cubes ...two different volumes...kept somewhere in the outerspace....take two elements in each of the cubes...the elements r still gonna be in equlibrium...but the magnitudes of the pressure actin on both the elemnts r gonna different right?...as pressure varies with volume....??

2. Apr 11, 2007

### lpfr

Try to write your post in english.

3. Apr 11, 2007

### nomorevishnu

wht do u mean?....r u talkin abt the typos?....guys, is the post not in english?...help with an answer someone please....

4. Apr 11, 2007

### Danger

Those are English words, sure 'nough, but the way that they're put together doesn't make a lot of sense. You've got a lot of partial information and partial questions, none of which add up to a coherent post. Try to rephrase it with all relevant parts included.

5. Apr 11, 2007

### Staff: Mentor

For starters, cubes of what and where is this pressure coming from?

6. Apr 11, 2007

### JoAuSc

Let me know if I got this right. There's this cube somewhere. Inside the cube, for any volume element dV = dxdydz, the pressure on one side of the element is equal to the pressure on the other side, for all three dimensions. This cube happens to be in equilibrium.

(I imagine it is possible to have a volume with a pressure gradient to be in equilibrium if there's an external force being applied that depends on position. For example, if we ignore the Earth's rotation and the heating of the sun, then the Earth's atmosphere would be in equilibrium, even though it would thin out as the distance R from the Earth's center increases. This is possible because of the Earth's gravity. I imagine the converse would be true too.)

I'm not quite sure what you were asking, but hopefully this helps.