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If you light a match in a spacecraft, which way will the flame go? Answered

Will it form a flame ball?

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acidbass (author)2010-12-06

no it will not.......well it could if you light it near the oxygen tanks but it should go straight up considering there is no wind unless you have people around you

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Kiteman (author)acidbass2010-12-06

Ahem - in orbit, no weight, so no convection to draw the flame up. The flame will form a sphere, and then go out, as diffusion cannot feed oxygen to the reaction quickly enough to keep the flame going.

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acidbass (author)Kiteman2010-12-06

the sphere i understand but wouldnt the fire keep going because there is oxygen

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Kiteman (author)acidbass2010-12-06

On Earth, you'd get a convection current - the hot, oxygen-depleted air rising and drawing in a steady supply of fresh oxygen-rich air.

With no convection current, oxygen only spreads by diffusion (look it up) which is much slower than convection.

That is also why spacecraft need fans - without breezes, people would suffocate in their own cloud of CO2.

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acidbass (author)Kiteman2010-12-06

ok ok I see now so it basically forms a "force field" (if you will) and dies under its own source
sorry american high school science sucks these days

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Kiteman (author)acidbass2010-12-06

Not a force field (that's gravity, magnetism and electrostatics), but a "zone of depletion" - any oxygen molecule that bounces too close gets eaten by the reaction, until the immediate area is empty, and the flame starves.

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acidbass (author)Kiteman2010-12-06

ah! even a better simplistic answer than mine :-)

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Kiteman (author)acidbass2010-12-06

BTW - $10 prize? The deadline is gone...

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acidbass (author)Kiteman2010-12-06

yes and i have found a winner

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