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CELS
15-12-2007, 13:39
Just wondering if there are any phycisists here who can tell me what would happen if a human (with or without armour) got hit by a melta-weapon. According to the wargear book from 2nd edition, there is a loud roar as their body moisture vaporizes, but I'm just having difficulties picturing what would happen if, for example, a Titan with a melta cannon aimed its weapon at a group of infantry. Would they simply disintegrate, would they catch fire, would they explode...? If hit from a long distance, is it possible that the soft flesh would disintegrate, while their skeletons remained more or less intact?

I know it's slightly grotesque, but I'm curious :)

He who is doom
15-12-2007, 13:54
think of getting hit by a melta gun like getting hit my a solid flow of super heated (beyond its normal temp) magma. the body would be a red poof in the super heat.

thats what i think of when i think hit by melta

Death Before Dishonour
15-12-2007, 14:12
i recon targets would glow white for a second super heated before instantly disintegrating, leaving little in the way of remains

BigRob
15-12-2007, 14:14
I seem to remember the description talking about Microwaves or something, might be totally off, its been a while since 2nd edition.

I always imagined a melta gun literally melting through stuff. A short ranged beam comes out of the gun and literally cooks whatever it touches, melting a hole though stuff. As for flesh and bone, thered be a hole punched though it the size of them beam, with the fles hdissolved and the edges cauterized.

Aladin_sane
15-12-2007, 14:27
I believe the weapon that draws a comparison closer to vaporization is a plasma shot if anything, super heated gas is hotter than any melta

Eisen
15-12-2007, 15:11
As I understand it, it'd be a lot like an RF burn on a massive, massive scale. You'd burn from the inside out, and by the time you actually felt it on that scale, you'd be dead. Bodies left behind would look a lot like a hot dog that's been microwaved for an hour and a half. The moisture-popping thing is an apt comparison, but I don't see the loud roar. Think of it as drinking from a radioactive fire hose.

I always saw the melta's effect on vehicles as being due to two effects, a huge, localized circuit-frying EMP that could cause some small internal explosions, and crew-cooking.

Mechanicus
15-12-2007, 15:35
The Imperial Munitorum Manual mentions that some melta weapons work by sub-molecular thermal agitation, whilst others work by fusion, with a pyrum/promethium mix.

Freak Ona Leash
15-12-2007, 16:20
The Imperial Munitorum Manual mentions that some melta weapons work by sub-molecular thermal agitation, whilst others work by fusion, with a pyrum/promethium mix.
In other words, they work because The God-Emperor tells them to.

Iracundus
15-12-2007, 16:23
From the 2nd ed. wargear book, the melta weapons are basically masers.

Pandir
15-12-2007, 16:28
There is a prt in Starship Troopers where a bug sprays this firey stuff on a guys arm it quickly starts melting, I always imagined it was liked that only quicker.

Icarus
15-12-2007, 16:29
I always got the impression it would burn a big hole through your body and the rest would be half burnt to crisp, but im not a physicist so...

scratchbuilt
15-12-2007, 16:33
Like the gremlin in the microwave.
In Gremlins

gLOBS
15-12-2007, 17:15
Word of the day is sublimation, Solid-->Gas.

CELS
15-12-2007, 17:36
Well, sounds to me like there's a clear absence of physicists in this thread. I'm happy to hear everyone's [uneducated] opinion, but I'm still looking forward to hearing from someone who knows. And more importantly, it would be great if someone could actually explain what happens and why.

UselessThing
15-12-2007, 17:49
Have you considered looking at pages about Nuclear Weapons - some must have details on what happens when you get flash heated to 3000 degrees. Might get the same overpressure effects as well.

Otherwise, might I suggest the melta gun scoring big channels of lava in everything it passes over.

Eisen
15-12-2007, 17:53
If you insist...

One of the dangers of working with transmitting radio antennae is that there is a strong electric field surrounding the antenna - has to be, it's broadcasting a radio signal. Contacting an RF transmission source is a very, very good way to cause damage that doesn't show on the surface, but rather manifests as a radiation burn beneath the surface. Antennae aren't the only place you'll see this - lightning strikes produce similar results, though the sudden change in resistance in the case of a lightning strike also produces a big release of thermal energy, plus lightning by definition has to travel through a very narrow path.

Now, we are handicapped in describing how a melta weapon actually works, because there have been, as described elsewhere, multiple melta types described. Some act as mini fusion warheads - I model some of my meltas as Panzerfausts based on this concept. Some are pretty clearly transmitting radiation of some kind - "sub-molecular thermal agitation" is a fancy way of describing this. These will produce the same kinds of effects as a radiation burn... which is exactly what I described above, though RF burns are very localized, very intense radiation burns (not to be confused with radiation poisoning).

You asked for an explanation as to why this happens - well, there are a couple reasons. If you want it at the atomic level, it's because pumping electrons into a system ALWAYS causes agitation, ALWAYS produces valence changes, and ALWAYS results in bonds being broken. The amount of change you get is based on how many electrons you pump in. The most common way of seeing this is water - the bonds holding water together are weaker than those holding the other atoms in a cell together, and the energy required to cause a state change (liquid to gas, for instance) in water is smaller than that required to vaporize solids.

Since you seem intent on qualified people responding... I spent four years as a radio operator. Two of those, and two past that, I was also the unit nuclear, biological, and chemical defense guy. For the four years FOLLOWING my radio-operator time, I've also been an engineering student, which includes more materials science than I ever wanted to take.

Mad Larkin UK
15-12-2007, 17:53
i Always imagine it would be like the new war of the worlds film heat ray, except clothes and armour would go poof aswell.

Eetion
15-12-2007, 18:09
Ok... my best guess... Im no pysicist but i will try.
Assuming that a melta works on the priciple of energising particles due to heat, all matter has a boiling, melting and freezing point.
Solid> Liquid> Gas
I would summarise that melta weapons energise particles of the target, so once struck the cells and particles become agitated and in the fraction of a second of the hit, the matter briefly transforms into a liquid state before evaporating as a gas.
So if the matter was a person, the flesh would momentarily liquify before dispersal as a gas. If the impact was a non essential body area, such as shoulder or arm, the result would not be immolation but essentially evaporation of the affected body part, this would allow bionic reconstruction and possible survival (doubtful) as per Lufgt Huron.

My opinion liquifiucation and evaporation in a very quick time scale.

Bunnahabhain
15-12-2007, 18:28
Just wondering if there are any phycisists here who can tell me what would happen if a human (with or without armour) got hit by a melta-weapon. According to the wargear book from 2nd edition, there is a loud roar as their body moisture vaporizes, but I'm just having difficulties picturing what would happen if, for example, a Titan with a melta cannon aimed its weapon at a group of infantry. Would they simply disintegrate, would they catch fire, would they explode...? If hit from a long distance, is it possible that the soft flesh would disintegrate, while their skeletons remained more or less intact?

I know it's slightly grotesque, but I'm curious :)

Eisen is right.

For the Radio Frequency type melt, it is essentially a directional, very high powered microwave. Just imagine putting a piece of meat in a microwave, and leaving it on high for and hour. Now have that happen in a second or two.


It's also not impossible. There are already recorded instances of Aircraft being downed as their electronics are overloaded by powerful radio signals, such as from flying too close large FM radio antennae.

A steerable and focussed beam is more dangerous. The best examples of this are AWACs type aircraft, which can have a power output of several Megawatts. Tightly focusing this on appraoching aircraft may be enough to score a soft kill, by disabling electronics.

Another possibility is to look at induction heating

http://en.wikipedia.org/wiki/Induction_heating

Which although not practical at range, is a good way to do catastrophic damage to things. As a side note, industrial induction furnaces, designed for melting metal, have been used by food manafactures to effectivley stir fry food, as they can cook things very fast, and at a high temepertaure, in the same way as stir frying, but in larger batches.

zeep
15-12-2007, 18:31
The 40k universe verifiably does not use our universes rules of physics. Nobody knows what would happen, other than crispy.

dark blade
15-12-2007, 18:43
when hit my a melta the person would be engulfed by a bright, short lived flash of light, scream a little, and all that would be left was a pair of smaking shoes, the underlying reasin to this is tha tit woudl not only be impressive, but also has that charicter to it, like, you really know that they where KILLED! :) lol

Wyatt
15-12-2007, 21:36
Take a plastic mini, and stick it in a jar of paint stripper. Take it out and stick it on a base, and you will have a melta-victim. :)

The way I have always seen it, is it melts everything - so your bones, skin, everything, would melt into goop. It wouldn't disintegrate entirely - much like when someone spontaneously combusts and ashes (and shoes) are left behind, except goop rather than ashes.

ctsteel
15-12-2007, 23:24
the guardsman raised his melta toward the roaring carnifex, quickly scrolling through the onboard menu settings to 'carnifex'. The melta settings for this menu item were to use 'high' setting for 8 seconds. he pressed 'start' and aimed.

shortly thereafter the melta chimed a loud 'ding' and a smoking pile of sizzling meat wafted its aroma over the squad.

5 minutes later they were all tucking into plates of tex-fex ribs and chilli-con-carni

(sorry) :p

Firaxin
15-12-2007, 23:31
I think the Japanese were experimenting with microwave beam weapons on live subjects during world war two rather than trying to make an atomic bomb. Thankfully, we finished the bomb long before they could perfect it.

So a melta weapon using radio/micro/x/whatever rays seems perfectly reasonable to me.

squiggoth
16-12-2007, 13:19
chilli-con-carni

Excellent.:D

azimaith
16-12-2007, 13:31
Meltas work in the dark age style, by molecular agitation (which essentially is "heating" with a fancy name) but apparently delivered by some form of electromagnetic energy and no solid/liquid/gas fuel source while others work by shooting a gout of superheated fuel like substances out, probably vaporizing them before flash igniting them.

I don't see it as being microwave, microwaves heat like anything else, from the outside in, but they operate by exciting water molecules, essentially steaming things, which renders them less than useful against tanks. Granted there are many many ways of heating things I don't see microwaves as one of them.

In either case you'd get a couple of factors.
One you'd get light as the heat increased to the point of combustion.
Two you'd get sound as the fuel igniting or the target began to cook.
Three you'd get a very high surface temperature very quickly.

In any case the target, being human as above, would catch fire and be immolated into dust rather swiftly, probably having little time to quite catch that hes been caught by a melta weapon before he's destroyed. The weapon discharge is probably noisy as vaporized gas catches fire and air temperature changes quickly but theres but otherwise you probably wouldn't hear anything else, they'd be quite dead before they could scream at all for a normal human.

However, targets near a melta discharge may very well catch fire and die in a rather unpleasant fashion. Its suprising the operator is at so little risk when the weapon itself is considered.

I've heard references of "Melta Tightbeams", I believe in Xenology which indicates theres probably quite a few molecular agitation models still out there. What sort of beam they put out is up for grabs. Anything that can excite molecules works, IE an electron beam would not only create heat as its kinetic force ionized particles it would also emit gamma and X-ray radiation (the long term effects of which I'm certain the Departmento Munitorium could care less about). So if I had to guess, with its short range and beam types, i'd say an electron beam works pretty well for that, you've got a stream of beta particles zapping out exciting most molecules and ionizing some. This creates heat in any target your hitting as well as X and Gamma rays (I suppose beta particles as well when considering certain types of ionizing events like characteristic X-ray production).

pom134
16-12-2007, 16:03
People keep mentioning microwave cooking, but haven't explained how the microwaves actually cause things to heat up.

The water molecules in your body are polar. Meaning they have an unequal distribution of charge across the molecule (more electrons are on the oxygen because it is more electronegative). The alternating wave form (positive and negative) of the microwave agitate the molecule, causing it to rapidly reorient itself depending on what region of the wave it is in (depending on if it's in the positive or negative region of the microwave it will prefer to have its electrons oriented in a certain direction).

The frequency of a microwave is between 300 MHz and 300 GHz. Thats between 300 MILLION and 300 BILLION peaks per second. Meaning those water molecules are reorienting themselves between 300 million and 300 billion times per second. The heating occurs because of the friction that occurs on a molecular scale. If the meltagun is using microwaves it would have to be alot more powerful than your home microwave to do what it says it does.

I agree with azimaith in saying that it probably isn't microwaves because most metals actually reflect microwaves. You could argue that the meltagun uses microwaves to superheat AIR and then shoots the hot hot AIR at things, but at some point that just turns into a plasma gun because superheated ionized air is just plasma.

Xgladar
16-12-2007, 16:23
If you've ever seen a tanker bug in the horrible movie adaptation of starship troopers.you know exactly how it should look like...

khirsath
16-12-2007, 16:53
While a high powered, focused microwave beam would be rather nasty for living tissue I agree that it is probably not what melta weapons use. For the record microwaves heat by sending EM waves at the harmonic frequency of water which makes the molecules vibrate faster and faster causing a build up in heat. Heat is after all the measure of how fast molecules/particles move. Eventually this can break the bonds and no you have free hydrogen and oxygen ready to react to all your other molecules. Microwaves do burn from the inside, don't believe me try eating a half thawed frozen burrito. There is a certain penetration depth where the microwaves are best absorbed. The effects on tissue from such localized interior heating would be organ failure, internal third degree burns. If it last long enough, or at high enough power, blistering will occur and your internal fluids rupture the surface. Its possible to focus the beam enough you'll have steam rupturing out of you as your fluids flash boil. But it is also possible that your internal heat can get to the point that things combust. which is why fires can start in microwaves if you try cooking them for too long.

This works well for standard organic matter (I'm not sure it would work on Nids as they seem rather impervious to radiation) but as stated earlier microwaves don't work well for anything but water. Actually the efficiency is terrible even for water ice. You should try rinsing a frozen item before microwaving it as it will defrost faster, but you could burn it. The reason that some metals can't be used is that the microwaves will induce a current with the surface electrons, the roughness of the metal on a microscopic scale determines how the current moves and if there are sparks. Sparks and currents are bad for your home microwave, but I doubt it would seriously affect a battle ready tank, at least not the way that meltas are supposed to. So if not microwaves what can a meltagun be?

While a beta-particle beam could do a lot of damage to metals and organics alike this is really just a sophisticated plasma gun. After all a plasma is defined by a composing of charged particles and can be ions, electrons, etc. It seems odd that the Imperials would have trouble sending a glob of plasma safely across a battlefield but have no problem with a tightly controlled beam.

It is possible that meltas are just focused EM beams and not waves, which would cause the induction heating and explain the short range. This would melt metal in much the same fashion as cutting torch. Molten metal flowing away from the impact sight. On organic matter it would cause severe burns and probably ignite the poor sap who got hit. Both of these are surface effects meaning that the thicker the armour the longer the beam would have to held in place to get inside the tank to damage the vulnerable parts.

Another option that occurred to me is that a melta is a cluster of multiple high powered lasers. There could be an aspect of it that is microwave, additionally there would be high energy UV, Xray laser to take on armour. The benefit of multiple frequencies is that each laser would penetrate to a different depth and effect. which would make the weapon ideal for multiple targets. The visuals of such high powered lasers would be the near instant vaporizing of metal, which may occur below the surface causing an explosion from the high pressure gaseous vapor. Not very good for vehicles I fear. Organic matter would suffer instantaneous radiation burns. If the beam is wide enough I could see it severing limbs or burning holes through people. A multimelta might just vaporize a person as well.

Well these are the first thoughts that ran through my head this morning. Which is, as I am a PhD student in physics, not that peculiar for me. I hope some of this helped

BlackLegion
16-12-2007, 16:59
There is nothing to be seen. You point the Melta towards the target, pull the trigger and it goes ssSBANG!!!!!!

pom134
16-12-2007, 16:59
It is possible that meltas are just focused EM beams and not waves



How can electromagnetic radiation NOT be a wave?

Gaz
16-12-2007, 17:03
I've always imagined it as a sort of WHOOSH......POP.


And then there was none.

I like to keep it simple :D

khirsath
16-12-2007, 17:06
Good question pom134:

It needn't be a self propagating wave of EM fields, i.e. light. It is possible to have non-self propagating EM waves, they just don't last that long. The electric field can be focused on a spot far away, though its difficult, an even more so with magnetic fields. I misspoke when I said beam as its more like focused fields, the idea is to get as much energy from the field into the smallest possible target, that way the field will over power the EM bonds of the target materieal.

pom134
16-12-2007, 17:15
Good question pom134:

It needn't be a self propagating wave of EM fields, i.e. light. It is possible to have non-self propagating EM waves, they just don't last that long. The electric field can be focused on a spot far away, though its difficult, an even more so with magnetic fields. I misspoke when I said beam as its more like focused fields, the idea is to get as much energy from the field into the smallest possible target, that way the field will over power the EM bonds of the target materieal.

So would that be like making a standing EM wave appear on the target 100 feet away? And as far as the energy required to start breaking bonds in materials you are going to have to go past microwaves.

Some surface and material characterization techniques use x-ray sources to eject electrons from the bulk of the material, and x-rays can have energies up to a couple thousand eV's. Microwaves are much less energetic, they aren't going to be breaking any bonds.

khirsath
16-12-2007, 17:58
So would that be like making a standing EM wave appear on the target 100 feet away? And as far as the energy required to start breaking bonds in materials you are going to have to go past microwaves.

Some surface and material characterization techniques use x-ray sources to eject electrons from the bulk of the material, and x-rays can have energies up to a couple thousand eV's. Microwaves are much less energetic, they aren't going to be breaking any bonds.

You're forgetting about harmonics with the natural vibration of the molecules. You keep this up long enough and the thermal energy is what breaks the bonds. Which is pretty bad for organic creatures. Metals, however need much more energy to damage. With x-rays you don't just want to strip electrons, you want to induce a high enough current that the metal melts. You want to increase the current so quickly that you overcome the metals ability to conduct heat away, this is basically how many forms of wielding occurs. Take aluminum and Titanium for example, they conduct heat away from a torch so efficiently that you heat the whole object up and can end up with a big pile of molten metal. If you can heat just a section up faster than it can deal with it you get molten metal only where you want it. The key is to focus the energy into a small spot. Which is hard to do from 30 meters away with today's tech.

Lord Nestron
16-12-2007, 18:20
Ok i am studying Medical Physiks in Europe.

here is how i would see it:

Molekuhl Agrigation isn`t an Unknown every X-Ray machine works on it. For all the People who don`t know it works here it goes : it means u super heat a Wolfram Coil to about roughly 1270 °k (kelvin) at that heat the elektrons on the outer hull go lose and are moveable this side is called the kathode (minus pole) and then there is a spining plate which is connekted to the kathode and is called athnode which is the plus pole and if there is enough currency between them the elektrons move overto the athnode ant enough speed to generate a electro magnetic wave spectrum what goes any where from heat to x-rays (about 1 % of it)

thats the easy explanation of molekuhl agrgation but the question is what happens zo the person. here is my theroie (never tried such high energie so i can only estamate what would happen) :

the water would boil and vaporize (in nano seconds)(you would die at this stage within 30-120 seconds) followed by your bodys fat then your skin would burn and at some stage the molekühls would have enough energie to break there bindings meaning you would just dissapear

ps. sry for the grammer and spelling

azimaith
16-12-2007, 23:08
So would that be like making a standing EM wave appear on the target 100 feet away? And as far as the energy required to start breaking bonds in materials you are going to have to go past microwaves.

Some surface and material characterization techniques use x-ray sources to eject electrons from the bulk of the material, and x-rays can have energies up to a couple thousand eV's. Microwaves are much less energetic, they aren't going to be breaking any bonds.
In the diagnostic range you'll generally see X-rays from about 50-150 KeV, in industry they can go into the MeV range.

Basically to eject electrons you need ionizing radiation which for the electromagnetic spectrum is going to start at ultraviolet and go up from there.

I don't see an X-ray beam being the primary culprit for a melta gun because x-rays have diverging rays. Thus you'd be collimating a very small cone of total production (as x-rays don't reflect, at least we don't know how to reflect them) thus would need ridiculous quanties of energy. Thats why I was emphasizing the electron beam style which, as written above is essentially the way an X-ray tube works, using thermionic emission from a tungsten coil and a negatively charged focusing cup to focus the electrons into a tighter package and sending them off, the cathode being essentially whatever you happen to shoot them at. From that you'd get alot of heat (99% heat, 1% Xray by current standards). Problems occur when we look at MeV's potentialled electrons crossing the gap, the higher you go in voltage the more X-rays you produce and thus the less heat you produce (as conservation of energy is at work) thus you can't really just increase kilo/megavoltage. I suppose you could heat it alot with a great deal of amperage with just enough voltage to harden the beam for its passage to the target.

Brother Siccarius
16-12-2007, 23:17
There is a prt in Starship Troopers where a bug sprays this firey stuff on a guys arm it quickly starts melting, I always imagined it was liked that only quicker.


If you've ever seen a tanker bug in the horrible movie adaptation of starship troopers.you know exactly how it should look like...

Actually that was a Bio-plasma, hence the form, function, and over-all effect of the blasts. Meaning it's a lot more like a Plasma Cannon, and a lot less like a Melta.
The effects are entirely different. Melta weapons being a beam-like line of effect that hits everything in a straight line from the barrel till it contacts something that it can't penetrate (Gaunt's Ghosts, BGB 3rd and 4th edition, Ciaphas Cain novels). A Plasma splash-like weapon is fired and terminates at the first thing it contacts but effects the area around the point of contact, size depending on the amount of plasma fired in one burst (BGB 3rd edition).


Meltas work in the dark age style, by molecular agitation (which essentially is "heating" with a fancy name) but apparently delivered by some form of electromagnetic energy and no solid/liquid/gas fuel source while others work by shooting a gout of superheated fuel like substances out, probably vaporizing them before flash igniting them.

I don't see it as being microwave, microwaves heat like anything else, from the outside in, but they operate by exciting water molecules, essentially steaming things, which renders them less than useful against tanks. Granted there are many many ways of heating things I don't see microwaves as one of them.

In either case you'd get a couple of factors.
One you'd get light as the heat increased to the point of combustion.
Two you'd get sound as the fuel igniting or the target began to cook.
Three you'd get a very high surface temperature very quickly.

In any case the target, being human as above, would catch fire and be immolated into dust rather swiftly, probably having little time to quite catch that hes been caught by a melta weapon before he's destroyed. The weapon discharge is probably noisy as vaporized gas catches fire and air temperature changes quickly but theres but otherwise you probably wouldn't hear anything else, they'd be quite dead before they could scream at all for a normal human.

However, targets near a melta discharge may very well catch fire and die in a rather unpleasant fashion. Its suprising the operator is at so little risk when the weapon itself is considered.

I've heard references of "Melta Tightbeams", I believe in Xenology which indicates theres probably quite a few molecular agitation models still out there. What sort of beam they put out is up for grabs. Anything that can excite molecules works, IE an electron beam would not only create heat as its kinetic force ionized particles it would also emit gamma and X-ray radiation (the long term effects of which I'm certain the Departmento Munitorium could care less about). So if I had to guess, with its short range and beam types, i'd say an electron beam works pretty well for that, you've got a stream of beta particles zapping out exciting most molecules and ionizing some. This creates heat in any target your hitting as well as X and Gamma rays (I suppose beta particles as well when considering certain types of ionizing events like characteristic X-ray production).

The effects you describe pretty much sums up the look and sound of it described in both the Ciaphas Cain Novels and the 3rd edition Rulebook.

The 3rd and 4th edition rulebooks describe the Melta as forcing an already volatile gas into a sub-atomic level, from this I infer that it could be either breaking it apart into pieces smaller than an atom, releasing a large amount of energy in the process, or somehow compressing the atoms of the gas into something smaller than the atom's original size (Something we'll never likely know and the Mechanicus may probably never find out).
This is kept contained within a containment field within the gun itself until fired, much like the plasma in plasma weapons is contained before firing. When fired the gas releases a large amount of heat, light, and general energy for a short range until the effect dissipates. However the only sounds described from it's effects are a high pitched hiss from vaporized moisture (water vapor I assume) and a roaring explosion when it contacts an object of sufficient mass (described as the "target" though it could very well be anything large enough and in it's way). The target has been simultaneously described as exploding and being turned into slag, depending on which account you read (Munitorium Manual, Main Rulebook, or Background novel).

DartzIRL
16-12-2007, 23:18
Like the Flash of a Nuclear Bomb, only a lot more concentrated... Close enough to it, anything that will burn will burn, anything that will vapourise will vapourise...

Since the heating effect tails off with the square of the distance, then it'll give an accurate reflection of the range too...

It's interesting to note though, that the human body does not Vapourise when superheated, it carbonises. All the volatile chemicals boil, or burn away in a flash, leaving only a perfect statue of pure carbon. Of course, this lasts for maybe a microsecond before the blastwave obliterates it and turns it to dust.

Carbonised person would have just enough time to wonder.. is it hot in here?

Over longer distances, clothes and skin will actually catch fire, and the victime will burn to death, in a slow, excruciating manner... until the blast got to 'em anyway.

Melta weapons should be a more concentrated effect of this... a concentrated beam of pure thermal energy, rendering metal to slag, and organic material to dust...

Smoking boots indeed...

azimaith
16-12-2007, 23:26
The 3rd and 4th edition rulebooks describe the Melta as forcing an already volatile gas into a sub-atomic level, from this I infer that it could be either breaking it apart into pieces smaller than an atom, releasing a large amount of energy in the process, or somehow compressing the atoms of the gas into something smaller than the atom's original size (Something we'll never likely know and the Mechanicus may probably never find out).

Well that would be pretty crazy to break down the gases into submolecular compounds (at which point they're no longer that molecule anyhow). I don't think this is exactly how it works because they generally mention either sub-molecular agitation or a gas mixture.

Still, that would be a mean gun, I suppose thats why my Elysians weild 11-13 of the buggers.

Brother Siccarius
16-12-2007, 23:48
I figure the various atom's reactions may be a bit more 'springy'. The Atom itself having been compressed into an unnatural state, when it's released from that compression it might release a lot of energy as the force of it's re-expansion sheds the various pieces from the atom, election flying off and creating a discharge of energy and protons and neutrons colliding with anything in it's path. Of course it's all speculation as we have yet to see anything like this happen, as we have very little experience in seeing atoms escape from a black-hole-like crushing force.

Kulgur
17-12-2007, 08:55
mmm according to the old Inquisitor rulebook, the target's vapourised in a blast of intense heat caused by microwave agitation created by a magnetic containment beam :)

MrBigMr
17-12-2007, 11:32
All the descriptions does support sort of maser. A hydrogen maser to be exact, but with different gasses. In Fire Warrior Kais gets his hand to on one and turns it against the bridge crew of an Imperial ship. Basicly it just melts stuff away into thin air and disintegrates people on impact. All at a very high rate. So a single sweep would be like wielding a big light sabre with infinite blade.

I've imagined it to be the same. An invisible beam of super heated air that just makes everything glow white hot and turns stuff into molten slag or piles of ash. Even if the beam itself doesn't engulf the target, the heat is so massive it'll burn a large area. Tanks would heat so that the ammo and fuel will detonate sooner than what the tank would melt.

Kymar
17-12-2007, 17:46
Though the whole Molecular Agitation and masers are cool, I think meltaguns simply release massive amounts of thermal energy.
My reason for this stems from the only "anti-melta" described in 40k, ceramite which is described as being heat resistant, not reflective to electromagnetic waves.

Meriwether
17-12-2007, 18:08
Credentials: I teach physics.


I think the Japanese were experimenting with microwave beam weapons on live subjects during world war two rather than trying to make an atomic bomb.

The Israeli's currently deny having a crowd-control weapon that uses a combination of microwaves and focused subsonic pulses to cause extreme and instantaneous nausea and cramping in subjects, but I've seen the video. It's neat and icky, and entirely non-fatal. 'Molecular agitation' indeed.


People keep mentioning microwave cooking, but haven't explained how the microwaves actually cause things to heat up.

Thank you for beating me to this. One thing that has always annoyed me about the melta weapon being a microwave (as it has been described for a long time) is that microwaves will *not* heat non-polar materials (like, for example, ceramite). However, most non-polar materials (like, for example, ceramite) would consequently be transparent to the microwaves, so you'd just cook the vehicle (and everyone in it) without harming the special coating... a lot like a 'microwave safe' coffee mug.


Though the whole Molecular Agitation and masers are cool, I think meltaguns simply release massive amounts of thermal energy.
My reason for this stems from the only "anti-melta" described in 40k, ceramite which is described as being heat resistant, not reflective to electromagnetic waves.

The problem being that 'release massive amounts of thermal energy' doesn't really mean anything. If it's already there to be released, the critter/tank is already that hot. If it _creates_ massive amounts of thermal energy, we're right back to the question of 'how?'

As to the OP, a super-intense microwave would essentially immediately convert all the liquid in the body to steam -- so as you were bursting into flames you would 'pop' like a hot dog in the microwave.

Mmmmm.... Yummy!

Meri

Brother Siccarius
17-12-2007, 18:36
Credentials: Sci-Fi fan

The above post is one of the reasons I don't think it's a Micro-wave emitter, but something more complex. The effects of the Melta are not invisible at all, in many/most places you actually see it depicted as a bright line with a brilliant explosion on reaching the target (in Art, Novels, Video games, and Rulebooks), alternatively the Melta-bombs being shown to produce large explosions.

The how of how a melta works is described in the Main Rulebook of both 3rd and 4th edition.

Burnthem
17-12-2007, 19:18
First off i want to say that the second i saw the words 40K and Physics in the thread title i feared the worst :D but to be honest this is one of the most grown-up and least flamed weapons technology threads i've seen in a long time. Keep it up :)

My two pence - i quite like how the Melta is portrayed in Fire Warrior, the 'beam' looking like an incredibly pressurised flame, but thats just IMO. As for HOW it works, i like to think of the pyrum/petrol gas theory, supercompressed/heated/charged volatile fuel that is released using magnetic fields, much like a plasma weapon, after all, what is plasma but super energised gas? So a Meltagun in my humble opinion is just a large and reliable plasma cutting torch, in fact its probably got a 'weld' setting on it :D

(IMHO)

Meriwether
17-12-2007, 20:09
I think that they have tried to get away from the microwave description (aaaah, the old 'cooker gun') as the years have gone by, especially *because* the original description doesn't make anything close to scientific sense.

Meri

pom134
17-12-2007, 21:01
The 3rd and 4th edition rulebooks describe the Melta as forcing an already volatile gas into a sub-atomic level, from this I infer that it could be either breaking it apart into pieces smaller than an atom, releasing a large amount of energy in the process, or somehow compressing the atoms of the gas into something smaller than the atom's original size

Thats nuclear fission buddy. Melta guns are not atomic bombs.

azimaith
17-12-2007, 21:25
Couple things, first off, not all parts of the electromagnetic spectrum are capable of being reflected. For example, X-rays, as we know them now, do not reflect off materials (that would taking an X-ray alot easier if it were.)

Next, i'm not certain on Microwaves, but I'm pretty certain they can't heat things much beyond the boiling point. Not sure on this one, I know more about X-ray/gamma ray emission/production over the opposite side of the spectrum.

Beyond that, meltaguns are generally known to melt tanks and the like, not simply cook crews, which makes the idea they fire microwaves rather unlikely.

Grindgodgrind
18-12-2007, 11:28
I always thought that a target would be dehydrated instantly and blasted into ash...

Meriwether
18-12-2007, 15:09
Couple things, first off, not all parts of the electromagnetic spectrum are capable of being reflected. For example, X-rays, as we know them now, do not reflect off materials (that would taking an X-ray alot easier if it were.)

That is not exactly true. A much more accurate statement would be: Different parts of the electromagnetic spectrum respond differently to different materials. What might be opaque to one EM wave might be transparent to another. *Most* materials are transparent to X-rays, and therefore cannot reflect them.

I personally know of two laboratories that reflect X-rays from some special materials that they made at the Laboratory for Laser Energetics (the LLE) at the University of Rochester. Currently they are trying to achieve directed reflection, as opposed to diffuse reflection, by modifying the characteristics of this groovy stuff they've made. I don't know how they're progressing, or what the real end goal is.


Next, i'm not certain on Microwaves, but I'm pretty certain they can't heat things much beyond the boiling point.

Sure they can, if you've got enough power. In any given moment, if energy in exceeds energy out and no mechanical work is being done, temperature will rise. So the trick is to make energy in exceed energy out by a LOT. You can do this with a whole ton of microwave photons, instead of just a few.


Beyond that, meltaguns are generally known to melt tanks and the like, not simply cook crews, which makes the idea they fire microwaves rather unlikely.

Agreed.

Good God, are we nerds. :D

Meri

dark blade
18-12-2007, 16:20
if i am being sereos (unlike my outher post) then i always picture the anti tank mines that my dad described to me (he is a bomb tec),

essentially you have a chunk of copper with a shaped charge behind it, when detonated the charge liquidises the copper and simultaniosly fires it at high velocety, the result is a molten copper slug going at considerable speed which then hits and melts strait through the target, of course for more effect the meltagun would vaporise the copper (or whatever).

the seocnd thought that i had was for something called a pig stick,
take a tube and seal one end, fill with water, place plastic piston in, put shotgun shell behind it, point and fire, the water is goting so fast that it ruptures the end og the pipe (weakened becouse of the sealing process) and fires out in a stream. this does not sound bad but the stream of water is, in effect, solid! as it cannon condence and has enough force to rip through a person at about 3 meters, (the plastic plunger will kill at about 30 meters :) ) now think about dong tis with fuel and it flashpointing at the moment of inpact, that is a meltagun!

Burnthem
18-12-2007, 18:01
if i am being sereos (unlike my outher post) then i always picture the anti tank mines that my dad described to me (he is a bomb tec),

essentially you have a chunk of copper with a shaped charge behind it, when detonated the charge liquidises the copper and simultaniosly fires it at high velocety, the result is a molten copper slug going at considerable speed which then hits and melts strait through the target, of course for more effect the meltagun would vaporise the copper (or whatever).

the seocnd thought that i had was for something called a pig stick,
take a tube and seal one end, fill with water, place plastic piston in, put shotgun shell behind it, point and fire, the water is goting so fast that it ruptures the end og the pipe (weakened becouse of the sealing process) and fires out in a stream. this does not sound bad but the stream of water is, in effect, solid! as it cannon condence and has enough force to rip through a person at about 3 meters, (the plastic plunger will kill at about 30 meters :) ) now think about dong tis with fuel and it flashpointing at the moment of inpact, that is a meltagun!

The copper charge is a armour piercing shaped charge, used in most anti-tank missile's, off-route mines, EFP's etc, it uses the Munroe effect of a shaped charge concentrating force and heat onto a particular point and although its very effective its not really suitable for a hand held weapon :) http://en.wikipedia.org/wiki/Shaped_charge

Metal gear Ray in MGS2 has a pressurised water cannon, it uses it to cut its way out of the cargo hold its inside. This would be rather a cool idea to base a weapon around, although the sheer amount of water needed to power the thing would be a hindrance. http://en.wikipedia.org/wiki/Water_jet_cutter

Meriwether
18-12-2007, 18:18
Dude, almost none of the weaponry in 40K is suitable for a hand-held weapon, just based on energy requirements alone... We have to assume a much higher level of technology to make sense of a lasgun being smaller than a tank...

Meri

Burnthem
18-12-2007, 19:48
What i meant was its not a good idea to be anywhere near a shaped charge when it goes off, let alone holding one in your hands :D

Lord Nestron
18-12-2007, 20:36
ok here is a idea of mine what if the wepon was after i just went and read all information on meltas i got it says quote: " a magnetic containment beam that creats atomic agrigation and vaporizisrlyis its taget" so it clearly says it creats agrigation on an atomic level no more discussion on that but of intrest is what they mean with "magnetic containment" but i might have an anwser to that ones again let me introjuce you to the world of diagnostics and to our x ray maschine it uses magnetic power to "create" x ray (not very good to admit it but hey) and to creat more pin point shots on the anode they use magnetics on the most basic lvl by puting a magnetic - poles all around the kathode with which you can force the electrons to hit the anode where you want or stop it all together (emergenzy stop)

Brother Siccarius
18-12-2007, 22:48
Thats nuclear fission buddy. Melta guns are not atomic bombs.
Actually, the two possibilities I presented on the written description of a Melta correspond to Fusion and Fission. The fusion theory being presented by the idea that it forces the atoms of the gas into a subatomic mass, well I take that back, it's essentially fusion in that it forces the atoms together into a much denser mass, but does not necessarily force them to combine.

What i meant was its not a good idea to be anywhere near a shaped charge when it goes off, let alone holding one in your hands :D
A shaped charge is more like a Krak Grenade or Krak Missile. Personally I think it's a combersome effect in that it relies on a lot of things to make it work correctly. The effects of a Plasma or Melta weapon could easily be described as such as it involves releasing a dangerous effect in a direction after being contained in some manor of containment field.

ok here is a idea of mine what if the wepon was after i just went and read all information on meltas i got it says quote: " a magnetic containment beam that creats atomic agrigation and vaporizisrlyis its taget" so it clearly says it creats agrigation on an atomic level no more discussion on that but of intrest is what they mean with "magnetic containment" but i might have an anwser to that ones again let me introjuce you to the world of diagnostics and to our x ray maschine it uses magnetic power to "create" x ray (not very good to admit it but hey) and to creat more pin point shots on the anode they use magnetics on the most basic lvl by puting a magnetic - poles all around the kathode with which you can force the electrons to hit the anode where you want or stop it all together (emergenzy stop)

So basically working like a mass effect of X-ray radiotherapy or Proton Therapy?

azimaith
18-12-2007, 22:54
That is not exactly true. A much more accurate statement would be: Different parts of the electromagnetic spectrum respond differently to different materials. What might be opaque to one EM wave might be transparent to another. *Most* materials are transparent to X-rays, and therefore cannot reflect them.

Theres quite a few relatively radiopaque materials for X-rays too, just about anything with a high atomic number tends to do that. Lead for example is quite good at absorbing them which is why our collimators, shielding, and grids are made of them. With visible light we tend to get alot of reflection off most things. X-rays can be blocked (well absorbed) but so far we can't get them to reflect off anything common place yet.



I personally know of two laboratories that reflect X-rays from some special materials that they made at the Laboratory for Laser Energetics (the LLE) at the University of Rochester. Currently they are trying to achieve directed reflection, as opposed to diffuse reflection, by modifying the characteristics of this groovy stuff they've made. I don't know how they're progressing, or what the real end goal is.
Thats neat, its probably too expensive to be put at a diagnostic range yet. The biggest real life goal would probably directed radiation therapies and diagnostic x-rays. Since X-rays are emitting from the anode in a isotropic fashion you end up with them going everywhere besides onto relevant anatomy, even with collimation you still end up with a wide angle. With the ability to reflect and focus X-rays you could utilize more produced X-rays allowing for less money to be spent on electricity, less exposure time, and the utilization of less photons to get a diagnostic picture (since you can focus them rather than relying on chance.) Less photons equals less absorbed patient dose.



Sure they can, if you've got enough power. In any given moment, if energy in exceeds energy out and no mechanical work is being done, temperature will rise. So the trick is to make energy in exceed energy out by a LOT. You can do this with a whole ton of microwave photons, instead of just a few.

I don't remember where I heard this, maybe other people have heard it too.



Agreed.

Good God, are we nerds. :D

Meri
Training as X-ray technologist :P.
And a nerd, double nerdy.


ok here is a idea of mine what if the wepon was after i just went and read all information on meltas i got it says quote: " a magnetic containment beam that creats atomic agrigation and vaporizisrlyis its taget" so it clearly says it creats agrigation on an atomic level no more discussion on that but of intrest is what they mean with "magnetic containment" but i might have an anwser to that ones again let me introjuce you to the world of diagnostics and to our x ray maschine it uses magnetic power to "create" x ray (not very good to admit it but hey) and to creat more pin point shots on the anode they use magnetics on the most basic lvl by puting a magnetic - poles all around the kathode with which you can force the electrons to hit the anode where you want or stop it all together (emergenzy stop)

What your talking about is the focusing cup, a negatively charged "muzzle" for lack of a better word in which the space charge (Electrons forced from a heated tungsten filament by like charges) are then prevented from spreading out in a "shotgun" effect by even more negative charges on the focusing cup.

Thus when the electrons are foced through the gap they stay close enough to be more of a beam like formation so they can hit a target a mm squared.

The magnetic containment field would probably just be a even bigger style of focusing cup used to shoot electrons in a certain area even more accurately. Thus I refer to my previous post about the electron beam idea. You fire a beam of electrons at the enemy (and if its a magnetic containment field it prevents the electrons from spreading out) which causes kinetic impacts that generate heat. (as well as X-ray radiation).

Mad Jack Deacon
19-12-2007, 14:57
I'm an English major and Art minor, who works as an Instructional Design Analyst. So I have absolutely no credentials with regard to determining how a melta weapon would theoretically work.

So.

I'm going with UNKNOWN TECHNOLOGY X!

That's why it works. It's like magic!

Mercer
19-12-2007, 15:04
The description in the battle of macragge rules says it melts things to molten slag, to everything would just become a molten pile of ash and slag.

The beam would be as big as the gun barrel, anything done to a vehicle would burn through the armour and cause a possible EMP due to the radiation.

Mercer

He who is doom
19-12-2007, 16:52
i found a description of a melta hit in "storm of iron" it says that the oxygen in the blood ignites in a poof of red steam as the body burns in an instant.

CELS
19-12-2007, 17:04
Well, the "red steam poof of doom" seems to be the winner so far. But a lot of insightful science mumbo jumbo so far. Thanks to the educated people out there, this thread has been more educational than I dared hope :)

fizban64
19-12-2007, 21:44
well it has been an interesting read ! I've always imagined melta and plasma as interchangeable, But I have had a break from warhammer since issue 103, gonna give it a spin with some of these undead necon beasts, hopefully christmas time.:cool:

Tyranid_commander
20-12-2007, 00:28
The melta weapon systems have enough heat to probably disinetgrate In short the following phrase would be acceptable.


WOULD YOU LIKE IT MEDIUM RARE OR EXTRA CRISPY!!:evilgrin:

RexTalon
20-12-2007, 07:51
Well, the "red steam poof of doom" seems to be the winner so far. But a lot of insightful science mumbo jumbo so far. Thanks to the educated people out there, this thread has been more educational than I dared hope :)

Yes, there have been some good ideas rolling around here. Eisen had it pretty much correct. I think the only thing he might have messed up was by saying that the electrons "bump up against one another". This is, of course, impossible.

I've worked with radios for 15 years and I've been a physics dabbler for just as long.

It's all about how much energy you can impart upon a thing. The melta gun has always been one of those weapons which would actually work given the right amount of power.

A microwave beam would impart enough energy, at lower levels, to cause the blood plasma to vaporize, which would kill the target instantly. However, it actually imparts quite a bit of energy. The moist innards of your bones would also vaporize. There wouldn't be a skeleton, because your bones would explode at the same time your flesh is vaporizing.

If it was used by a titan I would imagine that nothing would be left of infantry. Not only that, it would make quite a mess of the very ground. It might impart enough energy to melt the surface of the planet, turning it to glass, or magma, depending on it's makeup.

Meriwether
20-12-2007, 18:14
I've always imagined melta and plasma as interchangeable

I think the primary difference is that the melta gun heats up the target's molecules, while the plasma gun heats up some kind of ammunition (until it reaches the plasma state of matter) and then throws it at you.

Either way, sucks to be you!


I think the only thing he might have messed up was by saying that the electrons "bump up against one another". This is, of course, impossible.

Well... that depends on your definition of 'bump'. Electrons 'touch' in the same way that we 'touch' things -- they never actually come into physical contact, but they get close enough to exchange virtual photons.

So if you define 'bump' as 'exchange momentum through the exchange of virtual photons', then the statement is correct. (If you define it any other way, I'd be curious as to how you would do so...)


It's all about how much energy you can impart upon a thing.

...and how quickly. The funny thing is that there would be tremendous _recoil_ from a microwave-cooker-gun that could heat people up so quickly. I'm not terribly inclined to do the math at the moment, but throwing enough light at someone to cook them 'instantly' (say, in 1/100th of a second) would require a boatload of photons...

...and as weird as it seems, light carries momentum, so the gun would recoil.

Meri

Burnthem
20-12-2007, 18:44
...and as weird as it seems, light carries momentum, so the gun would recoil.

Meri

Dude, if this sentence kicks off another 'Do Lasguns have recoil?' thread you deserve to be banned :D

RexTalon
20-12-2007, 20:43
...and as weird as it seems, light carries momentum, so the gun would recoil.

Meri
But has no mass, so no.

Emperor's Grace
20-12-2007, 21:15
But has no mass, so no.

Isn't it "next to none"?

Otherwise, impulse engines and light/solar sails wouldn't work :D

azimaith
20-12-2007, 21:22
Yes, there have been some good ideas rolling around here. Eisen had it pretty much correct. I think the only thing he might have messed up was by saying that the electrons "bump up against one another". This is, of course, impossible.

Dude, electrons have mass, they're particles, we've calculated them. Electrons do not equal photons. Maybe i'm missing what your saying.



It's all about how much energy you can impart upon a thing. The melta gun has always been one of those weapons which would actually work given the right amount of power.

Well the melta is essentially a "heat ray"



A microwave beam would impart enough energy, at lower levels, to cause the blood plasma to vaporize, which would kill the target instantly. However, it actually imparts quite a bit of energy. The moist innards of your bones would also vaporize. There wouldn't be a skeleton, because your bones would explode at the same time your flesh is vaporizing.

The problem is it does this with water molecules which may not be sufficient to cause great heat in short amounts of time against non-organic targets and in dry environs.


I think the primary difference is that the melta gun heats up the target's molecules, while the plasma gun heats up some kind of ammunition (until it reaches the plasma state of matter) and then throws it at you.

Either way, sucks to be you!

Well we also don't know how melta weapons work exactly.



Well... that depends on your definition of 'bump'. Electrons 'touch' in the same way that we 'touch' things -- they never actually come into physical contact, but they get close enough to exchange virtual photons.

We know we can get electrons to move with sufficient kinetic energy to ionize atoms of practically any material. But electon does not equate to photon if thats why your saying. Case in point beta particles ionize atoms by knocking electrons out of orbital shells.




...and how quickly. The funny thing is that there would be tremendous _recoil_ from a microwave-cooker-gun that could heat people up so quickly. I'm not terribly inclined to do the math at the moment, but throwing enough light at someone to cook them 'instantly' (say, in 1/100th of a second) would require a boatload of photons...
Actually it depends on the quality of the photons.



...and as weird as it seems, light carries momentum, so the gun would recoil.

Meri
Light doesn't carry any kinetic energy, its energy. Any recoil from a lasgun would be from mechanical means, not from the emission of photons.

RexTalon
21-12-2007, 08:17
0.0000000000000006 electron volts isn't much of a mass and is hardly worth worrying about when you're talking about the kick of a las or meltagun. True that the melta would have to be pretty damned powerful, but it still would have hardly any kick.

RexTalon
21-12-2007, 08:22
Well the melta is essentially a "heat ray"
Heat is the byproduct of what is occurring at the molecular level, yes. It's the radiation of the energy imparted upon the molecules by the passing of high frequency particles.


Actually it depends on the quality of the photons.
I use only ACME brand photons in my lasgun.


Light doesn't carry any kinetic energy, its energy. Any recoil from a lasgun would be from mechanical means, not from the emission of photons.
There would be kick at very high power, but it would be negligible. A photon has mass, but it's so low that we consider it massless.

Meriwether
21-12-2007, 14:53
Dude, if this sentence kicks off another 'Do Lasguns have recoil?' thread you deserve to be banned :D

LOL. The answer is trivially, 'Yes, lasguns have recoil because of the law of conservation of momentum'. The question is, how much? (I'll visit that in a bit.)


But has no mass, so no.


Dude, electrons have mass, they're particles, we've calculated them. Electrons do not equal photons. Maybe i'm missing what your saying.

And photons don't have mass, but they do have both momentum and kinetic energy.

*Puts on teacher hat and glares for silence...*

Look kiddies, I hate to burst your collective bubbles, but the nice little equations we learn in high school (p=mv and KE = 1/2*m*v^2) are approximations. The actual equations take into account that massless particles (such as photons) do in fact carry momentum, and do have kinetic energy. This is weird and counter-intuitive and screwed up, but it is also absolutely true. Not only have we proved it, but we use it in various technologies.

Specifically for photons, the kinetic energy of a photon is equal to planck's constant times the frequency of the photon, while the momentum equals that energy divided by the speed of light.

Any given photon has a tiny, tiny amount of momentum. But you need lots and lots (and ***LOTS***) of them in order to 'blast' anyone with them.

Ok, in spite of my original intentions, I've done the math. Your typical 75-kg Imperial citizen would take two hundred million Joules of energy to flash-boil, assuming they are mostly water, which they are. (Note, that isn't 'reduce to component atoms' or 'melt the metal they have on their bodies' or any such thing, just flash-boil the person. That is, take all the water in their bodies from room temperature (20 deg C) to 100 deg C, then evaporate that water. So this is an 'evapogun', not a real 'meltagun'...)

Your typical microwave has an energy of 1x10^-21 Joules, so you'd need two hundred billion billion billion photons of microwave frequency, each carrying 5.7x10^-30 kg*m/s of momentum. This translates into about 1.00 kg*m/s of recoil, which is about 1/3 the recoil of an HV .22-caliber round -- seems very reasonable, doesn't it? It isn't... Read on!

Assuming that we flash-boil them 'instantly'... Let's say, in 1/100th of a second... That means that the force on the shoulder of the evapo-gun wielder would be 96 Newtons, or about 22 pounds of force... ...and would consume twenty billion watts of power in that 1/100th of a second.

Here's a few of the problems: The energy needed to completely vaporize every bit of them is over ten times that. That means ten times the recoil (ow, but manageable...) and ten times the force (really, really ow -- like getting hit by a linebacker at full sprint), as well as ten times the power (which is the real problem... It isn't enough to just provide the energy, you have to do it _fast enough_).

Even at twenty billion watts... the nuclear power plant that powers the school from which I am typing this uber-nerdy missive is the Gannet Nuclear Power Plant, a 4.0 megawatt reactor on the shores of Lake Ontario. That means you'd need fifty of them operating simultaneously to fire an 'evapogun', and five hundred of them to fire a true meltagun -- almost 10% of the entire power usage of the United States, released in 1/100th of a second in the form of microwaves.

...and all of this is assuming: No friction, no heating of the gun, no heating of the air in-between, no ambient cooling of the target. All of these are systematic errors in our calculations, all of which, if taken into account, would increase the required energy, recoil, and power usage.

We have a name for a device that releases this kind of power: we call it a 'bomb'.

Meri

P.S. The lasgun only has to burn a hole through the person, and not completely evaporate them... So it would have maybe 1/100th of the recoil and 1/100th of the power requirements.

P.P.S. The Omega Laser that the University of Rochester fires for about one picosecond (a thousandth of a trillionth of a second), is as large as a building, and for that moment puts out more power than the US grid. It takes hours to re-charge the capacitors, and is the most powerful laser in the world (for now). It's the size of a factory.

Brother Siccarius
21-12-2007, 22:23
Of course, this could simply be that it's Sci-fi, or that it's not intended to be a microwave gun at all. As whenever I hear the idea of it firing microwave radiation, it just leaves me ever more perplexed as to how the mechanism described in the main rulebook turns around to it firing microwaves.

Meriwether
02-01-2008, 17:44
Right. The original fluff was entirely unambiguous: it was a microwave gun. They've since gotten a lot more vague about how it works, and probably because of nerds like me.

...note that the power calculations above are independent of how it works, though.

Meri