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congratulations

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hello to donald boyer from ashland ohio

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donald says

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i've always wondered about fire in a

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zero gravity environment if you could

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light a match in your spaceship with the

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match uh fire tip go upward as it does

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down here with gravity or would it just

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become a round ball of fire since

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there's no gravity around the flame or

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does gravity have any effect on fire

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and

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could demonstrate it for you um but they

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won't let me lay

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any fires up here unfortunately

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uh but it's um well what happened you

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know the the thing that happens in

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in uh

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on the earth is that gravity and um and

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convection due to

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due to the density of air depending on

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its temperature causes the the flame as

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you see it so in other words

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when when

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when the fire heats up the air the air

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expands and that air that's expanded now

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is a lower density than the air that's

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around it and so the lower density air

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flows up just like a hot air balloon

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wants to go up it's

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it's a it's a volume with a lower

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density so the air around it basically

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points he pushes it up

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so what happens is the hotter air wants

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to rise and the colder air then comes in

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beneath the flame and that that creates

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a convection which drives the flame

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and of course the air that's closest to

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the flame is always hottest so that

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convection keeps going and causes the

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flame to to

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do the interesting things that it does

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up here

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of course the air that's closest to the

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flame would get hot

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but it would have no reason to rise

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because it's not light i mean it's not

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lighter

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you know than the cold the colder air

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around it

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the gravity is not going to have that

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effect here so the hot air it does

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expand and it would basically expand

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into the ball and it would push the

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other other air away

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you know symmetrically more or less

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and

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so the two things from that one is you

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don't get you know a flame that that

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would rise and look like a flame on the

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earth but also what happens is

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um it is the fire essentially puts

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itself out because as the

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warm air expands you know the oxygen is

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burned up inside that sphere

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and there's no convection to bring new

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oxygen back into where the flame is so

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what you'd expect

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here with a flame is that a flame would

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burn itself out

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and hopefully that's

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a benefit for us up here with a lot of

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electrical systems and everything that

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unless you have some kind of circulation

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to bring new oxygen to a

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fire or flame