# Thread: forgive me. ive always wondered

1. ## forgive me. ive always wondered

what if you got a huge round tube made out of plastic hard plastic and the walls of this tube were air tight. the hole will be the size of a football field(the two holes at each end of the tube). and the ozone has been sucked out of the tude. would it be like a vacume and suck all the air out from the earth. and if it could be done could you make a smaller one and as it is sucks the air out you could let go of it and it will just float in the air. the pressure would have to be equal.but maybe it is, if it wasnt then there would be no air. space would suck it all out.i wonder if the gravity of earth is equal to the pull of space(gravity keeps everything from floating away earth is OUR sorce of gravity, what if it keeps the air on earth. if this is true then the vacume of space has to be equal to the pull of gravity)..i may be stupid but eh. "i was gonna get up and find the broom" lol...im keepin it on the downlow..lol im sorry
Last edited by Chunky; 2006-Jun-20 at 01:40 AM.

2. The air does not stay on Earth because of the ozone layer, it stay on Earth because air is heavy. It may not feel like it, but the weight of the air above your head is so much that the air around you exerts tends of thousands of pounds of force on your body.

3. Originally Posted by johnathan
what is you got a huge round tube made out of plastic hard plastic and air tight. the hole will be the size of a football field.
Hole? You said it was airtight. Do you mean the volume enclosed? But, the volume of a planar football field is zero. Maybe a cross-section of the enclosed volume has the area of a football field?

Originally Posted by johnathan
and the ozone has been sucked out of the tude. would it be like a vacume and suck all the air out.
Just the ozone, leaving all other atmospheric gasses?

Originally Posted by johnathan
and if it could be done could you make a smaller one and as it is sucks the air out you could let go of it and it will just float in the air.
What is it that is sucking out the air? Oh, now you're removing air, not just ozone. OK. Yeah, if the mass of the air-tight container is small enough, and rigid enough to maintain the volume, then as you evacuate its contents, it will become bouyant. That's difficult, though. Easier is to insert a low-mass gas of equal pressure to the air, like hydrogen or helium, to maintain the shape.

Originally Posted by johnathan
the pressure would have to be equal.but maybe it is, if it wasnt then there would be no air.
You're losing me.

Originally Posted by johnathan
outer space would suck it all out..
You're really losing me. How did outer space get involved?

Originally Posted by johnathan
i wonder if the gravity of earth is equal to the pull of space..i may be stupid but eh. "i was gonna get up and find the broom" lol...im keepin it on the downlow..lol im sorry
Uh... Anyone else?

4. I think he is thinking the ozone layer is some sort of wall that prevent the atmosphere from being sucked into the vacuum of space. Assuming that is the case I dealt with it in the post directly before yours.

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Originally Posted by TheBlackCat
The air does not stay on Earth because of the ozone layer, it stay on Earth because air is heavy. It may not feel like it, but the weight of the air above your head is so much that the air around you exerts tends of thousands of pounds of force on your body.
there is that experiment where you heat up a oil can(with some water in it) thus displacing the air in the can with steam, you put the lid on it and then let the can cool down as the steam condenses you are left with a partial vacuum in the can and the can is gradually crushed by atmospheric pressure.

6. You don't need to go that far. Empty a soda can then put a little bit of water in it. Have a pan full of water on the stove and boil it. Have a saucepan or basin or something full of cold water right next to it. Place the soda can in the pan full of boiling water. Once steam starts coming out of the mouth of the soda can, use tongs (NOT YOUR HANDS) to quickly flip it over into the basin full of cold water so the can is now upside-down with its mouth an inch or so underwater (be careful to stand back so you don't spill any water on you). It will instantly implode as the water and steam in the can quickly contract when they hit the cold water. It is an easy and amusing trick you can do with only household objects. Kids should not use the stove under any circumstances, parents need to handle the boiling of the water and watch the proceedings very carefull. Kids could probably use and apron or jeans at the very least and long-sleeve shirt to keep boiling water off themselves just in case.

7. air would not be heavy if it wasnt for gravity..like...the earth weights nothing. because it is surrounded by nothing...or...im just thinking out loud but hey i made some touchups to the thread so it may help you understand what im asking...but maybe not

8. Don't confuse weight and mass. They are not the same thing.

9. im not confusing weight and mass.nothing has weight without the intervention of gravity. like, how much does a nickel weigh, on earth it is 5 grams but on the moon it is less and on jupiter it weighs more but in space it weighs nothing.sence gravity verys planet from planet wouldnt you call it..unstable?

10. Originally Posted by johnathan
im not confusing weight and mass.nothing has weight without the intervention of gravity. like, how much does a nickel weigh, on earth it is 5 grams but on the moon it is less and on jupiter it weighs more but in space it weighs nothing.sence gravity verys planet from planet wouldnt you call it..unstable?
No. It is a perfectly calculable function of mass and distance. The weight of your nickel changes because the mass of the planet doing the 'pulling' is different, not because of any instability of 'gravity' per se.

Calling it unstable is like saying the colour Red is unstable because an apple looks different in bright sunlight compared to when you are in dark cellar.

11. does anyone understand what im asking in this thread? just like a vaccume would suck water out of a bowl would a tube penitrating the ozone with all the ozone gasses sucked out of the tube at first...after all the ozone gases were out of the way. would space suck out all the air on earth. i have wondered this since junior high

12. Originally Posted by johnathan
does anyone understand what im asking in this thread? just like a vaccume would suck water out of a bowl would a tube penitrating the ozone with all the ozone gasses sucked out of the tube at first...after all the ozone gases were out of the way. would space suck out all the air on earth. i have wondered this since junior high
I think what you are asking, if one took a huge tube that went from close to the ground, through the ozone layer, to outer space, would the air be sucked through the tube, into outer space.

If that is what you are asking, the answer is no. As has been said, the ozone layer is not holding the atmosphere in, there is no "lid" to this pot. The gravitational field of the Earth and the mass of the atmosphere itself hold it "in place". None of that would change with some big tube.

13. No, it wouldn't suck the air away.

Think of the air as being really old milk. (No wait...I'll tie it in)

When you first get milk it's all one color and mixed in very well. as it gets older it starts to separate. After a while it has split into three disinct layers. There is the heavy thick layer at the bottom, the watery milk layer in the middle and the very thin water like layer at the top. I think that's how you are seeing the atmopshere. A layer of regular air with a layer of Ozone floating on the top. The problem with your interpretation is that, like that thin layer of stinky milk water, the ozone layer isn't going to keep anything from getting in or out (UV not included). If there were no Ozone layer, the Earth would still have an atmosphere becasue the gravity is pulling the air down to the surface.

The 'vacuum' of space isn't a vacuum like you use on a rug. It's not actually sucking anything. Basically, evertything hates crowds. Bob the Air Molecule wan't to have as much room as he can get so he will move to a more empty place unless something keeps him in the crowd. A balloon is a good example. Inside a balloon the air has pressure. It's a higher pressure than the outside air, so when a balloon is onpened the air rushes out. It's the skin of the balloon that keeps the air in.

The Earth's gravity is similar to the skin of the balloon. When Bob decides it's too crowded in the balloon, and he sees the opening, he rushes to it. Nothing is pulling him out. Once Bob is in the air, he wants to move off to space, but he can't because gravity is just too fascinating to him. He HAS to stick around. If, all of the sudden, the earth were replaced with a huge sphere of "frozen smoke" It's gravity would be reduced to the point Bob would leave and no lousy ozone layer could stop him. To an observer Bob is BLOWN into space by the rush of other air molecules wanting more room, just like him.

14. Bob the Air Molecule?

Actually, air mostly consists of Olivias and Nicks, but they're just friends.

15. i understand. but...say you get an actual balloon and fill it with air and you take the balloon with you into space once you got the balloon outside the shuttle would it expand? if so that would mean that space is kinda like a vacuume and if this is true wouldnt the gravity of earth have to be equal or greater than the 'pull' of space....maybe

16. im thinking of gravity as being exactly oposite as space...because it is. space has no gravity and the only reason air has weight is because of gravity produced by earth and its mass.the post that i posted before this one does it make since because it seems like it does

17. Originally Posted by johnathan
i understand. but...say you get an actual balloon and fill it with air and you take the balloon with you into space once you got the balloon outside the shuttle would it expand?
It would expand and one of two things would happen. One, the compressive force of the ballon would eventually balance the expansive force of the air and the balloon settles into a new, larger size. Two, the expansive force of the air is too great for the balloon and it would pop.

if so that would mean that space is kinda like a vacuume and if this is true wouldnt the gravity of earth have to be equal or greater than the 'pull' of space....maybe
As others have mentioned, there is no "pull" of space. In the case of the balloon, it's not space that is pulling on the balloon and making it expand, it's the pressure of the air inside.

18. Originally Posted by johnathan
i understand. but...say you get an actual balloon and fill it with air and you take the balloon with you into space once you got the balloon outside the shuttle would it expand? if so that would mean that space is kinda like a vacuume and if this is true wouldnt the gravity of earth have to be equal or greater than the 'pull' of space....maybe
Yes the balloon would expand if you took it outside the shuttle, but not because space is 'sucking' it's because Bob (and Olivia and Nick and the rest) see there is NO ONE else out there and they want to get some of that room for themselves

To put it in more formal terms, at sea level the air presses in on everything at 15 pounds per square inch. This isn't a stright down pressure like being sat on, it's an all around pressure like a bear hug. This pressure comes from the huge volume of air being pulled down by gravity. When you fill a balloon you may get 30 PSI into it. The skin of the ballon sqeezes in with say 20 psi, and the air pressure squeeses in with another 15. When you open the valve on the ballon that pressuer squeeses the air in tha ballon until it rushed out of the hole. It's not being sucked out. When you take the ballon into space where there is NO air pressure, then only that 20 PSI worth of squeeze from the balloon's skin is working to hold that 30 psi in. The ballon expands and pops. If the ballon had 20 psi in it, is would still expand but wouldn't pop. It would be stretched to the absolute limit though. Once the valve is opened, the air in the balloon has all of space to fill so it rushed out to find that bit of nothing it can call it's own.

If this doesn't work I have an airplane, bus, cruise ship, or subway/Tube/El train one that I just worked up.

And Swift... All my examples feature Bob and Jill. That way I can keep the pronouns different and not have to say something like, "So when Dave and Fred went to the store, he went to get eggs while he waited in line." It made a martial arts project I did a LOT easier, then it just seemed to stick with me. That Bob gets around.

19. well for the air to expand there would have to be something with less pressure outside the balloon (space), who says it cant be both. if there wasnt any activity(there is a better word just dont know it) in space, if it was null of all pressure or sucksion. the air wouldnt want to go any where it would stay where it was.there are two sides of a coin, ying-yang. maybe without space there would be no need for gravity.gravity compresses and space expands like heat expands metal and cold does the oposite.. there is a good chance i flipped my nut because i have been up all night. im probably talking stupid

20. and also with the balloon say you didnt air it up all the way and you just put a lil but of air in it. not enough to make the balloon walls expand. would it still expand. if it does than that proves it......maybe i dont know but i do like debating even if im wrong, i love you all

21. a lil bit of air in it******......bit not but

22. There is a term called osmosis. It basically means that 'stuff' will move from an area of greater concentration to an area of lesser concentration. Since air molecules have no free will, they can't really decide to do anything. Since they're not alive, they aren't subject to instict. They fall back to osmosis to control them.

Let's say that you have 100 million air molcules in a balloon. The volume of the balloon is 1 cubic inch. That's a concentration of 100,000,000/CuIn in the balloon. The air in the balloon is moving. It's only a little bit, but it's moving. It will move until it runs into something. It could be the skin of the balloon, or another air molecule. Either way, the further it can move the better.

Now let's say that we take the balloon and open it in a box with a volume of 100,000,000 cubic inches. The air will move into the box and spread out so that each molecule has one whole cubic inch to itself. Now the air has a concentration of 1/CuIn.

If we open the balloon to the emptiness of space, each molecule will have billions of cubic MILES ot itself. The concentration at that point is basically zero. At any rate it is so small that the measurement would be practically impossible to tell from zero.

23. Moved from "BABBling" to "Q&A".

24. Originally Posted by johnathan
and also with the balloon say you didnt air it up all the way and you just put a lil but of air in it. not enough to make the balloon walls expand. would it still expand. if it does than that proves it......maybe i dont know but i do like debating even if im wrong, i love you all
I'm not sure where you live, but there are ways to test this yourself. Are there any mountains near you when you can go 2,000 feet or more (say 600 meters) higher than your house?

If you can make a trip like that, get three balloons. Fill one almost full and tie it off. Fill the second one about half way, maybe to about the size of an orange or grapefruit. Don't fill the third one at all, just tie it off, but don't squish the air out first. Toss them in the back seat of the car with some drinks and sandwiches and head up the mountain. When you get up to a higher elevation, there is less air pressure around you. This is becasue the air pressing down on you is less since you're above a lot of it. Since there is less pressure, all three balloons will be bigger. The biggest will have probably popped on the drive, possibly scaring the driver and causing an accident. Maybe the full balloon is a bad idea....

Anyway the other two will be bigger. Even the one that you didn't fill at the beginning will be bigger. The airpressure in it will make expand against the lower pressure of a higher elevation. If you were ab;e to drive all the way to where the shuttle flies, the balloons would get even bigger because the outside pressure gets smaller until it reaches almost zero, while the pressure in the balloons stays the same. In space there is just nothing to squeeze 'stuff' so 'stuff' is free to expand until it hits something. This doesn't prove that there any type of suction in space, just that there is nothing squeezing.

Where I live we are at about 4200 feet above sea level. Potato chips (crisps) that are packaged at seal level will often have the bags pop when they reach the stores here for this same reason. Although, since I was at work when I saw them, and that store sucked....

25. Originally Posted by Tog_
There is a term called osmosis.
[nitpick]It's diffusion in this case, osmosis would be for water but it's more or less the same thing so it's bordering on moot for the purposes of explaining it [/nitpick]

Edit to fix quote tags

26. In a nutshell... If you built a tube from sea level to space, and opened both ends, the pressure gradient would mimic that of the atmosphere itself. Sea level pressure at the bottom and zero at the top.

27. Originally Posted by Tog_
Potato chips (crisps) that are packaged at seal level will often have the bags pop when they reach the stores here for this same reason.
Where, exactly, is seal level?

28. Originally Posted by Gillianren
Where, exactly, is seal level?
I know sea level changes, but as all mountains are measured in height above sea level, and ocean depth below it, There must be an acceptible average.

The chips in question were bagged in Los Angeles, which may be above the water most of the time, but it's still a great deal lower than my house.

And point taken on the osmosis thing. I'd neber heard it applied only to water. One of the standing jokes by teachers when they saw anyone with their head down on thier book, "Learning through osmosis." Guess it stuck with me.

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Originally Posted by Gillianren
Where, exactly, is seal level?
it's where the crisp packets are sealed. :wink:

30. Where, exactly, is seal level?

It's slightly above sea level so they can sit on the rocks.

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