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Move a match slowly and nothing happens but if you shake it violently the fire will extinguish. Oxygen makes fire grow so why does waving a flame through the oxygen rich air put the fire out? Does this primarily have to do with a decrease in temperature to the burning materials or is it something else?

Also what about forest fires, do high winds spread or kill the fire?

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  • $\begingroup$ A burning oil well is blown out with the mounted engine of a jet fighter. Done in many cases after Bush's first war against Irak. $\endgroup$ – HolgerFiedler Feb 1 '16 at 5:51
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    $\begingroup$ Crossposted from chemistry.stackexchange.com/q/44526/7890 $\endgroup$ – Qmechanic Feb 1 '16 at 13:01
  • $\begingroup$ Side note: remember that the flames you see are not the location of combustion. Visible flame only happens when the combustion products cool by emitting photons after the combustion event has completed. $\endgroup$ – Carl Witthoft Feb 1 '16 at 14:07
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Check out this question here: Why does a candle blow out when we blow on it? Our breath is 16% oxygen and only 4% CO2

Basically when you shake the match violently you move the fire away from its source of fuel. The flames themselves will have some momentum which you can see from the way the flame "tilts" as you move the match. When you move the match very quickly you move the source of fuel faster than the flames can readjust course.

In addition when you move the fuel source away from the flame, the fuel source will cool down rapidly and the combustion reaction will no longer be able to take place.

With respect to forest fires, winds will spread the fire because the flames are simply too much to really be blown away. that being said, for smaller fires you can still blow them out to some extent. Check out this video: https://www.youtube.com/watch?v=uyGDxglTVgA

Obviously that uses water as well, but you notice that when the jet engines turn on the fire goes right out whereas before nothing was really happening.

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  • $\begingroup$ I would clarify that the important point of "flames" is heat. The chain reaction is on-going because the heat released by the chemical reaction is in close proximity to more fuel. When you move the match, the heat gets spread out, and the chain-reaction can be broken. $\endgroup$ – Dave Cousineau Jul 25 '16 at 19:27

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