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Science questions answered for laymen

Discussion in 'General Chat' started by It's Snake Pliskin, Jul 15, 2009.

  1. It's Snake Pliskin

    It's Snake Pliskin

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    This thread can be for science questions we laymen might have regarding science.

    First question:

    In the vacuum of space that would be encountered in an Earth orbit would:

    a. a water bubble or oxygen bubble (gas bubble) move in an undirected way without evident force?
    b. a water bubble or oxygen bubble (gas bubble) move in a direction evident as though it had force propelling it?

    This scenario could be applied to, say a space walk or inside a vehicle capable of carrying man. Even these guys:alien2:
     
  2. jonojpsg

    jonojpsg

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    I like it - a science nerds thread:D

    I would have thought that the Brownian motion of the water molecules inside the droplet may impart some motion on the droplet, BUT the net force of the molecules hitting the inside surface may in fact be zero.

    A great video of water in zero g -

    http://www.youtube.com/watch?v=cXsvy2tBJlU

    PS How do I embed a video in a post?
     
  3. skyQuake

    skyQuake

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    Ok I'll bite:

    First of all there would be no such bubble, the vacuum of space would make it explode.
    Excluding centrifugal force, I don't think theres any force propelling it in any specific direction. (assuming it doesnt fall out of orbit)
     
  4. Naked shorts

    Naked shorts

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  5. It's Snake Pliskin

    It's Snake Pliskin

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    Thanks skyquake.:) So a gas bubble would burst or a water bubble would burst or both? Wouldn't the water bubble just float like in the video posted aboove by jonojsp? Thanks jono.:)
     
  6. It's Snake Pliskin

    It's Snake Pliskin

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    Thanks Naked shorts. So on Earth an oxygen bubble in water that rises rather quickly is propelled by what force?
     
  7. spooly74

    spooly74

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    If it's in Earth orbit it would have a force acting on it, Gravity. How long it stays in orbit depends on its speed.

    Air is lighter than water.
     
  8. Buddy

    Buddy

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    If I understand your question correctly........ the answer is buoyancy as explained by Archimedes Principle, which is in summary caused by the differential pressure forces (due to the water) at the top and bottom of the bubble.
     
  9. It's Snake Pliskin

    It's Snake Pliskin

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    Thanks Spooly. Is there gravity in the vacuum of space?

    For example:

    An air bubble comes from the helmet of a cosmonaught as he is doing a space walk. Would that bubble explode? or move because of the gravity force of the Earth due to being in orbit?

    And more importantly what would become of that cosmonaught?

    Thanks Buddy.
     
  10. Naked shorts

    Naked shorts

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    Gravity.
     
  11. Naked shorts

    Naked shorts

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    The bubble of liquid water would turn into a gas if exposed to the vacuum of space. This is because there is no pressure forcing the molecules together.
     
  12. It's Snake Pliskin

    It's Snake Pliskin

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    Thanks for your input.
     
  13. Buddy

    Buddy

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    Aah, gravity. It's everywhere, it's everywhere!

    It wouldn't really "explode", more like disperse into the vacuum of space. The "air" is subject to exactly the same gravitational forces as the guy with the helmet.

    Gotta watch those peskie Russian cosmonauts. If the "air bubble" is under significant pressure, the Ruskie might find himself going backwards at a significant rate of travel. Newton's laws and all that. :D
     
  14. happytown

    happytown

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    galaxies 'collide' and merge courtesy of gravity, eg NGC 5257 & NGC 5258 (currently in the early stages of a cosmic meet 'n greet)

    cheers :)
     
  15. Gillie

    Gillie

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    Would've thought that the bubble of liquid water would freeze before it had time to turn into gas and escape into the vacuum of space, as long as there were no sunlight, hence there is a force holding the molecular chains together. The real temperature in space is about 3 °K (-270 °C or three degrees Celsius above Absolute Zero). Absolute zero is the temperature in outer space without any sunlight. In sunlight the temperature can rise to 120 °C/ 250 °F (So typically the liquid water bubble would be turned gaseous). There are still molecules in space just very few of them.:cool:
     
  16. skyQuake

    skyQuake

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    A ball of ice exploding?

    Depends how the ball of water got up there in the first place.
    Hollywood has imprinted too much floating globs of water in space stereotype :(
     
  17. Gillie

    Gillie

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    Well, if you think of it, comets are exploding balls of dirt and ice. The coma and tail of the comet is the ice evaporating into space when heated by the sun on it's approach.
     
  18. jono1887

    jono1887

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    How about a new question... if you were to travel at the speed of light, is it possible to travel back in time?
     
  19. Gillie

    Gillie

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    Not according to relativity.
     
  20. skyQuake

    skyQuake

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    Yup, that water was already attracted to the comet by gravity and was already frozen.

    However if you magically get a 'ball' of water into space, would it freeze first or dissipate or explode?
     
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