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i was wondering why the hell las cannons have recoil absorbers when their is no recoil buy shooting light
any thoughts? if not could do some cool conventions or some thing

Maybe the recoil absorbers aren't for the recoil of the gun, but the recoil of the mechanism that produces the shot. I mean, I know the way that lasers are produced conventionally with our technology that there aren't really moving parts like that, as such. But maybe in the 41st millennium there is.

death by monkeys could be right.

It could also be that the 'light' builds up into a concentrated ball before being realeased, and the 'presure' release causes some sort of reverse force same way as a shaken up pop bottle has a 'recoil' when the tops taken off. Would explain the 'crack' of lasguns.

it could also be another of GW's oversights....

The model looks cool. Stop overthinking it.

Ah, but who says they're recoil absorbers? Ray guns throughout history have had little ring bits to look all futuristic. Maybe they're field boosters or something.

1. Who says LAS weapons have NO recoil?
2. Who says said part is a recoil absorber?

Otherwise this stupid trend started 92 i belive, when the spacemarine dev's were released.
Before that our beloved lascannon had no stupid recoil absorbers/barrel shroud/ fiddything.

They are ray shielding bands to reinforce and protect the actual laser emitter.

It is also possible they are heat sinks. Lasers are hot.

heatsuk is an interesting theory, seems to have the right look to it... but then again you would need some seious heat sheilding on that puppy though, cuz the heat thrown off by something that powerfull... I dont care if you have super-duper mastercrafted artificer terminator armour with a really ballsy pdf built in, that kind of heat could leave a pretty nasty mark. Fire it a few times and you are workin on gettin the nickname "nub" (no arm) or maybe even "tinman" (robo arm).

I've had lasweapon recoil worked out in my head for quite some time. When the concentrated light energy fires, the oxygen inside the barrel ignites and is forced out the end of the barrel, creating both the muzzle flash AND the recoil of the las-weapon.

I'll go with Sketchbooks interp. Super-heated Air./plasma needs to be dissapated with an equal/opposite reaction.

E=Mc2.

I could put the equation here....

Probably the most famous scientific equation of all time, first derived by Einstein is the relationship E = mc2.

This tells us the energy corresponding to a mass m at rest. What this means is that when mass disappears, for example in a nuclear fission process, this amount of energy must appear in some other form. It also tells us the total energy of a particle of mass m sitting at rest.

Einstein also showed that the correct relativistic expression for the energy of a particle of mass m with momentum p is E2 = m2c4 + p2c2. This is a key equation for any real particle, giving the relationship between its energy (E), momentum ( p), and its rest mass (m).

If we substitute the equation for p into the equation for E above, with a little algebra, we get E = gamma mc2, so energy is gamma times rest energy. (Notice again that if we call the quantity M =gamma m the mass of the particle then E = Mc2 applies for any particle, but remember, particle physicists don't do that.)

Let's do a calculation. The rest energy of an electron is 0.511 MeV. As we saw earlier, when an electron has gone about 10 feet along the SLAC linac, it has a speed of 0.99c and a gamma of 7.09. Therefore, using the equation E = gamma x the rest energy, we can see that the electron's energy after ten feet of travel is 7.09 x 0.511 MeV = 3.62 MeV. At the end of the linac, where gamma = 100,000, the energy of the electron is 100,000 x 0.511 MeV = 51.1 GeV.

The energy E is the total energy of a freely moving particle. We can define it to be the rest energy plus kinetic energy (E = KE + mc2) which then defines a relativistic form for kinetic energy. Just as the equation for momentum has to be altered, so does the low-speed equation for kinetic energy (KE = (1/2)mv2). Let's make a guess based on what we saw for momentum and energy and say that relativistically KE = gamma(1/2)mv2. A good guess, perhaps, but it's wrong.

Now here is an exercise for the interested reader. Calculate the quantity KE = E - mc2 for the case of v very much smaller than c, and show that it is the usual expression for kinetic energy (1/2 mv2) plus corrections that are proportional to (v/c)2 and higher powers of (v/c). The complicated result of this exercise points out why it is not useful to separate the energy of a relativistic particle into a sum of two terms, so when particle physicists say "the energy of a moving particle" they mean the total energy, not the kinetic energy.

Another interesting fact about the expression that relates E and p above (E2 = m2c4 + p2c2), is that it is also true for the case where a particle has no mass (m=0). In this case, the particle always travels at a speed c, the speed of light. You can regard this equation as a definition of momentum for such a mass-less particle. Photons have kinetic energy and momentum, but no mass!

But then, people might say..

Hey, I thought that was Nurglitch...............

damn thats some serious physics lol. makes me wish my teacher just didn't play guitar in the corner of the room.

think i may animu mine with wires round the coils for lulz. maybe "las" weapons ionize particles?

Yea, I agree with Sketchbook.
I also got a bit of a chubby from Akira's explanation. I kind of miss my physics days.

akira, the only modern physics I've had was in physical chemistry, and its been a while, so let me see if I have this straight...

The bottom line here is that you're saying p=E/c right?

That implies that the momentum of a photon of a given energy is much less than the value for energy. Furthermore, that implies to me that the momentum of a single photon is dependent on the frequency right since E = hv ( Where v is the frequency, am I remembering this correctly)?

We havent taken power into consideration yet, correct? Wouldnt that be what would really matter as far as the recoil?

For what it is worth, I vaguely remember doing a calculation in class, years ago, where we found how long it would take a astronaut to use a flashlight beam to travel a certain distance in space. I also understand that some folks have had the idea of using light pressure to propel spacecraft like sails and wind.

Given that a lascannon can cause catastrophic kills fairly easily on tanks with (presumably) more advanced armor than we have now, it must have to be able to deliver a great deal of power. I would think it may have a non negligible recoil, though certainly less than a projectile weapon relying on throwing mass downrange.

Grignard, agreed. Particle Mass Drivers could never get the same result, but pretty darn close as far as we are concerned anyway.

What about "lasers" that only use the laser part to ionize the air, and then rely on a directed electric strike to go down that ionized channel to destroy things, essentially a little lightning bolt?
I have read about that as a possibility, but never really much hard crunch on it.

I'm not sure that would have the destructive power of the lascannon, as I have heard of such a hypothetical technology being proposed as a less lethal crowd control weapon, sort of a long range stun gun.

A laser weapon might ionize the air anyhow....I can't remember if that would be wavelength dependent, power dependent, or both.

I also would think that the lascannon might not be a visible light laser. Perhaps it could be tuned to different frequencies depending on whatever your target is made of, and what you want to do. One might imagine this is how the Eldar stuff like the brightlance would work.

Hey wait! I know the part about the visible beam! (first paragraph that's made sense in this thread to me for the last few posts...)

The Laser from Las-weaponry is, by default, NOT visible. However! They have all been modified to create a bright red beam for the benefit of the Guardsmen firing them, to act in the same role as tracer rounds of old. Guard snipers often 'customize' their Long-Las rifles to remove this tell-tale beam that would otherwise lead to their doom...

I have NO idea where I read that from, but I'm pretty sure it was about snipers. And official, I swear.

I would suspect the laser would super heat the air as well, perhaps making the excited air particles (as well as any more solid particulates therein) release wave lengths that would be visible.

Either that, or an extreme version of heat distortion over asphalt in the summer

As well as producing that characteristic FWEEM! sound.

- Salvage

I thought it was "Pew Pew?" Or is that just the little ones?

Pew! is for the small lasers, that inexplicibly always miss our heroes.

- Salvage

Only inexplicable to you vile heretics.

Obviously the Emperor protects his chosen children. (Jedi or no)

i personally prefer wat! wat! wat! sound for my lasers, much more like the x-wings laser cannons

Do any Star Wars fanatics know where Lucas came up with the blaster sound?

actuality no i don't but if you do I'd like to learn why!

I used to know where they got most of the sounds from Star Wars. For some reason I want to say the laser (blaster) was a piece of rebarb smacked against a big metal bar, then sped up (I think). Don't quote me on that.

But Lasguns are clearly "Pew pew pew!". Personally I always play Lascannons as the same, but with only one 'pew' and MUCH deeper.

It's worth it to note, I think, that alot of the books mention the 'tell tale crack of las rounds ionizing the air'. I imagine they are somewhat reminiscent of an electric whip cracking. Probably nowhere near as loud as solid shot weapons.

yea i always imagined lasguns sounding like someone being slapped on the back when their wet

Grignard wrote:Do any Star Wars fanatics know where Lucas came up with the blaster sound?

They plucked the guy wires on antennas.

Too funny! Now is that for the standard storm trooper blaster's or for the space ship weapons? because those were more wat wat, rather than the hand held guns pew pew.

I always thought it was a shroud of some sort. Las weaponry is repeatedly stated to be solid state, so your laser is using a huge mass of PN junctions to step down current and releasing photons. Depending how efficient your setup is, it would get hot quickly, and need cooling gear. Obviously this stuff would get gunk caught up in the field, so they put a rubber shroud on it to keep the works clean.