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Thread: Do lava and fire burn the same?

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    Default Do lava and fire burn the same?

    Does anyone know if a 2000 degree flame is an adequate way to test how quickly and badly different substances would burn in 2000 degree lava? If not, how quickly would leather, cotton, wood, and human (or hypothetically elf) flesh burn in both lava and fire of the same temperature? And hi y'all, I'm new here.

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    Elen síla lumenn' omentielvo What Exit?'s avatar
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    Welcome to Mellophant.

    Lava is going to be a large heat generator and cause flesh to burn before contact. Leather would burn on contact. It is likely to start burning below 1000°f. There are gloves today that can just about handle 2000°f but made from some very high tech textiles. With lava comes poisonous gas, hydrochloric acid, potentially steam burns and a few other nasty and deadly ways of killing you.

    For the fire it depends on the size and time but exposing your hand or feet to a really hot fire for even a short time should cause severe burns. Flesh takes extended exposure though to ignite as we humans are about 60% water. Though by 1400° the flame is pretty much immediate.

    I hope this helps a bit. Anything beyond this detail is beyond me.

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    Oliphaunt Jizzelbin's avatar
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    That's a pretty good question.

    If i were drunk and thought my recently-passed first-year-college-physics-with-calc could expand on What Exit?'s answer could be better, trust me, I would.

    As What Exit? correctly highlighted, this is a material-science question. As far as I know, you just look it up in a ginormous book. How did the people make the "book"? I don't know, but you create a standard, by arbitration, and calibrate.

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    ....That sounds like it'd require a lot of math. Where exactly would I find this book? O.o

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    Elen síla lumenn' omentielvo What Exit?'s avatar
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    Quote Originally posted by Draconess25 View post
    ....That sounds like it'd require a lot of math. Where exactly would I find this book? O.o
    You can find a lot of it on-line but it gets confusing (to me at least) determining the lowest flash point vs. where it will surely catch fire. I'm lucky I can use the table to determine how much weight a pine 2"x4" can support. On top of that different lava actually had different temperature ranges as does different fuel sources for fires. The next biggest factor is time of course, but without some sort of high tech suit or magic* even the least hot of lava type will burn flesh and even leather nearly immediately and given a little time just being close. The 2000°f mark is interesting as the Navy had suits to deal with this temp back in the 1950s IRC.

    See page 9 of this PDF for what they can do with Zetex now.

    Not directly related to your question but talking about extremely hot fires:

    When fighter jets catch fire the flames get so hot that water is useless and even fire fighting foam doesn't usually work. The fire fighting training I went through said the only good way to deal with such fires was to push the jet off the flight deck and let it suffocate beneath the water. To make things more fun even fully submerged they burn for a while. I suspect the air force deals with these fires by isolating the jet and letting it burn and setting up a perimeter of fire fighting foam. The reason for the very hot fires was that the jets were made with magnesium alloys IRC.

    * please see Clarke's Third Law.

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    Administrator CatInASuit's avatar
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    Hi there.

    Depends on what kind of flame you are looking at. A candle flame hits about 1000C which is roughly the same temperature as a cooler lava flow, but no-one is going to suggest passing your fingers over a lava flow. The thing to consider is how much potential energy the source contains and can transfer to the object as opposed to just the temperature. For instance, If you get a candle and hold your fingers over it by the wick at its hottest (don't actually go and do this, it's purely hypothetical ), then its gets hot, might burn a little and be generally unpleasant. Doing the same on a lava flow is going to result in loss of hand.

    Without a very large fuel source, I'd hazard a guess that using a flame isn't a great comparison.
    In the land of the blind, the one-arm man is king.

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    Oliphaunt Jizzelbin's avatar
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    Quote Originally posted by Draconess25 View post
    ....That sounds like it'd require a lot of math. Where exactly would I find this book? O.o
    Yes, it would require a lot of math. But math are funny!

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    Oliphaunt Jizzelbin's avatar
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    Quote Originally posted by Jizzelbin View post
    Quote Originally posted by Draconess25 View post
    ....That sounds like it'd require a lot of math. Where exactly would I find this book? O.o
    Yes, it would require a lot of math. But math are funny!
    Actually, to take things as seriously as *What Exit?*, we need matrix algebra for this one. AKA "linear algebra." And why do we need it? Well, we just do, is all.

    We need to be able to quantize over many variables. So, that's the answer. Am I a mathematician? No, I am not. I'm not even very good at creating proofs But, I'm the closest thing you've got. that was an asshole answer -- sorry about that. well, at least you got an honest answer -- apparently I'm an asshole but at least you got an honest answer. Eh, as far as I know I told the truth.
    Last edited by Jizzelbin; 19 Oct 2015 at 06:22 PM.

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    Oliphaunt Jizzelbin's avatar
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    Quote Originally posted by CatInASuit View post
    Doing the same on a lava flow is going to result in loss of hand.
    "You don't know me!"

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