What is fire?
What is fire?
(OP)
I had my 5 year old asking me if fire is solid, liquid or gas.... I couldn't answer.
What would your answer have been?
What would your answer have been?
<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying " Damn that was fun!" - Unknown>>





RE: What is fire?
Perhaps that is too advanced for a 5 year old...if I had a 5 year old, I probably would have said that fire is a chemical reaction and isn't an element in and of itself.
The ancients said there were four elements: fire, earth, water, and air. Sadly, none of those are actually elements.
Cedar Bluff Engineering
http://cedarbluffengineering.webs.com
RE: What is fire?
I'll let you translate that one for a 5 year old. But you can think of hot metal that an ironworker is pounding on or liquid metal at a metal foundry, they both glow red.
Cedar Bluff Engineering
http://cedarbluffengineering.webs.com
RE: What is fire?
RE: What is fire?
David
RE: What is fire?
Cheers
Greg Locock
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RE: What is fire?
I disagree. Some of what appears to be a fire really isen't anything more that highly heated gas (izonized). Which can occur with out a fire.
So I would say the apperence of a fire is the light from a chemical, nucular, or electrical discharge reaction.
RE: What is fire?
RE: What is fire?
So what I tried to do was get iron hot enough to show her the glow. Damn pine wood, did not get hot enough and she got bored.
So in conclusion, was I right on fire being gas at a very high temperature emitting a glow as what photoengineer says? It would have to be the glow emitted by N2, I guess, but then comes having to explain the different colourings of the different elements when they burn.
Something somehow doesn't sit right thinking fire is overheated gas. I might be wrong though
<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying " Damn that was fun!" - Unknown>>
RE: What is fire?
Steel wool and a battery, or a clear light bulb so she can see the filament when the bulb is off, and again when on. Even cooler if you can vary the voltage with a dimmer and show the filament with a dull red glow. Then have her touch the bulb (ouch, thats hot)(yes, much hotter than your body). Stuff has to be really, really hot to glow.
You and I say "duh" to the above, but to a 5-year old it can be a revelation.
RE: What is fire?
RE: What is fire?
What do flames look like in zero gravity? Do they even self-sustain? The combustion products would not naturally move away from the fuel.
- Steve
RE: What is fire?
To a five year old: fire is hot gas produced by something burning. You get fire when you combine something which burns, air or something else that has oxygen in it, and something to get it started like a little fire, a spark or something really hot. Fire makes heat, but some fires don't make light that you can see! And you can also use electricity to make light from a gas, and the gas doesn't even need to be hot!
RE: What is fire?
http://sc
see pic
RE: What is fire?
RE: What is fire?
Magnificent!
If (and it is very unlikely) I ever resort to theism, fire will be high on my list of things that drew me to it.
- Steve
RE: What is fire?
RE: What is fire?
The green light radiated from our sun is exactly the same reason as why molten steel is red and a propane flame is blue. The material is at the right temperature to emit red, green, or blue light. Propane gas is on fire (oxygen is combining with propane), while molten steel and our sun are not burning.
The light emitted from flame is a characteristic of the temperature of the gas. The fire itself is a chemical reaction.
Cedar Bluff Engineering
http://cedarbluffengineering.webs.com
RE: What is fire?
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: What is fire?
It's getting towards that time (in the Northern hemisphere) when candles should be lit.
If I were a physics/chemistry teacher, candles would provide a lot of my teaching material.
- Steve
RE: What is fire?
RE: What is fire?
<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying " Damn that was fun!" - Unknown>>
RE: What is fire?
I say this by the way it conducts electricity.
RE: What is fire?
RE: What is fire?
As someone in the chemical business might appreciate, there are several exothermal reactions that do not require the O2 in the air. Such might be the case of Magnesium and water. And there are several more.
Cranky, I did not know fire conducted electricity, quite interesting. But so do many other gases. This characteristic not necessarily makes it plasma, does it? I had an initial thought that fire could be plasma, but then inclined more into the gas theory.
Ok, I guess I was not the only one that could not answer to a 5yr old!
<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying " Damn that was fun!" - Unknown>>
RE: What is fire?
Flame, which is what some people are trying to define here, is the visible manifestation of (some) fire. It can be a plasma, depending on the temperature and gases involved, it can also just be very hot (un-ionized) gases.
RE: What is fire?
Also I discovered this when I was younger with a light match and a bug zapper.
RE: What is fire?
RE: What is fire?
RE: What is fire?
RE: What is fire?
I would say that flames are a gas, heated to the point of glowing. How you heat the gas is not relevant. It can be a match. It can be the sun.
You will have to explain somehow that hot things glow, and that they glow a certain colour at a certain temperature.
RE: What is fire?
Cold things glow too. Just not at a wavelength we can see.
(Hence...night vision goggles.)
Cedar Bluff Engineering
http://cedarbluffengineering.webs.com
RE: What is fire?
RE: What is fire?
I thought night vision gogles worked off low light provided from other sources. Do they work in underground conditions?
I remember burning alcohol in chemistry class, and there was no visible flame. It did however burn my lab partners hand.
RE: What is fire?
Sure, why wouldn't all objects (that have a temperature above absolute zero) emit radiation? Hot objects emit radiation in the visible light range. Colder objects emit radiation that is of a longer wavelength.
Cedar Bluff Engineering
http://cedarbluffengineering.webs.com
RE: What is fire?