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Author Topic: what happens to a candle in a falling lift?  (Read 3646 times)

paul.fr

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what happens to a candle in a falling lift?
« on: 23/11/2007 23:33:23 »
if the lift was falling from height, say 20 floors up, would the candle go out?


 

Offline Karen W.

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what happens to a candle in a falling lift?
« Reply #1 on: 23/11/2007 23:50:21 »
I would think with the air swooshing up and from the bottom up past the flame, that it would stay lit. because it wasn't hitting the flame from a crosswise angle at the flame.

Are you going to do a test???
 

another_someone

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what happens to a candle in a falling lift?
« Reply #2 on: 24/11/2007 00:38:57 »
If the lift is falling at a constant rate, than the air will be falling at the same rate, and so there is no relative motion.  As the lift accelerates, the flame might grow slightly due to the reduced effect of gravity.

If there was a massive rush of air (which normally is not the case in a sealed lift, although it might be the case if you were using an exposed lift, e.g. a fireman's lift, or the type of thing window cleaners use to clean the windows of tall buildings), then the cooling effect of the air might quench the flame.
 

Offline lightarrow

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what happens to a candle in a falling lift?
« Reply #3 on: 24/11/2007 01:37:36 »
If the lift is falling at a constant rate, than the air will be falling at the same rate, and so there is no relative motion.  As the lift accelerates, the flame might grow slightly due to the reduced effect of gravity.

If there was a massive rush of air (which normally is not the case in a sealed lift, although it might be the case if you were using an exposed lift, e.g. a fireman's lift, or the type of thing window cleaners use to clean the windows of tall buildings), then the cooling effect of the air might quench the flame.
What happens should be the equivalent of a candle in a no-gravity place; they studied such little flames inside the Shuttle, with no-gravity and it turned out the flame is spherical and smaller, because of lack of convection; in that situation oxygen can come in contact to the combustible only through diffusion and so the process is much slower.
 

Offline neilep

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what happens to a candle in a falling lift?
« Reply #4 on: 24/11/2007 02:32:42 »
if the lift was falling from height, say 20 floors up, would the candle go out?

Don't forget to actually light the candle !!


 

lyner

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what happens to a candle in a falling lift?
« Reply #5 on: 25/11/2007 00:27:29 »
Unlike most candles, you would have to blow it to keep it alight!
 

Offline lightarrow

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what happens to a candle in a falling lift?
« Reply #6 on: 25/11/2007 15:40:06 »
Unlike most candles, you would have to blow it to keep it alight!
Exactly.
 

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what happens to a candle in a falling lift?
« Reply #6 on: 25/11/2007 15:40:06 »

 

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