Electromagnetic vs Kinetic Energy

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Discussion Overview

The discussion centers on the effectiveness of electromagnetic (laser) versus kinetic energy (projectile) weapons, particularly in military applications. Participants explore the impacts of both types of weapons on various targets, considering factors such as energy delivery, armor penetration, and operational contexts like vacuum versus atmosphere.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Exploratory

Main Points Raised

  • One participant questions the effectiveness of a 530 MJ IR laser pulse compared to a 155mm projectile with the same energy, particularly regarding their impacts on lightly and heavily armored targets.
  • Another participant argues that conventional weapons may be more reliable, suggesting that an IR laser could be easily countered by a silver coating, while noting that X-ray lasers would pose a different challenge.
  • Some participants express a preference for kinetic energy weapons like railguns or coilguns over lasers, citing their proven effectiveness and potential for future development.
  • A participant raises the issue of how the duration of a laser pulse could affect its impact, speculating that a longer pulse might result in burning through a target, while a very short pulse could cause an explosive effect.
  • Discussion includes a mention of the U.S. military's development of directed energy weapons (DEWs) and the potential advantages of lasers in targeting fast-moving objects.
  • Another participant expresses skepticism about the objectivity of previous posts, suggesting that the term "effective" may not equate to "devastating," and highlights the advancements in smart projectiles.

Areas of Agreement / Disagreement

Participants express differing views on the effectiveness and practicality of laser versus kinetic energy weapons, with no clear consensus reached on which is superior. The discussion remains unresolved regarding the specific impacts of each weapon type on various targets.

Contextual Notes

Participants reference various assumptions about energy delivery, target materials, and the operational environment, but these assumptions are not universally agreed upon. The discussion also touches on the limitations of current military funding and research priorities without reaching a definitive conclusion.

easyrider
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Looking at this in a weapon point of view, what would be the more effective one?

Say we have a 155mm projectile traveling and hitting a hard target(metallic), lightly and heavily armored, at different times, both with an impact energy of 530 MJ.

Also say we have a very short IR laser pulse with a beam diameter of 155mm also hitting lightly and heavy armored targets, with an energy of 530 MJ.

What would be the effects of each in a vacuum? Would it change very much to do it in atmosphere (besides the associated drop in velocity with more range for the projectile)?
The projectile most definitely seems it would be much more devastating but I just wanted to get some realistic answers on this.
 
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What a laser! 530 MJ!
Let's put aside the huge amount of energy and analyze pros and cons of conventional and laser weapons.
An IR laser can be easily defeated by applying a silver coating. Certainly, a lot of the coating would be vaporized but the target would be largely unharmed.
If we had a X-ray laser things would be different since X-rays can´t be stopped that easily. Thirty years ago, Edward Teller "sold" this idea to president Reagan who funded the project heavily. The result was a complete fiasco. Go and buy a good powder-powered cannon. It´s heavy, beautiful and it makes a lot of noise.
 
I agree, what is already being used definitely fills the need and is optimal. Railguns/coilguns seem like a better choice for future weaponry imo than lasers.

But okay, let's throw out the energy values, if a laser and bullet of equal size/energy hit and went through the roof of a ww2 half track from above with intention of knocking out the driver, would the effects of each be very much different?

Also, how would a laser of fairly high irradiance act on a fleshy target?
 
easy rider:

I know little about laser weapons except that they ARE being developed; So I have my doubts that the posts so far are objective. "effective" might not be the same as "devastating", but it SEEMs as if the projectile would do the most damage once it hit. An apparent advantage of new projectiles is that they are "SMART"...self guided or remotely so.

you might find this brief discussion of interest:

http://en.wikipedia.org/wiki/Laser_weapons#Military
 
I know that we, as in USMIL (Im in the Army), are developing all kinds DEWs. I don't know what you mean by "not objective"? IMO lasers definitely have their place, especially in anti-aircraft, anti-satellite, and all around long range weapons used against high speed moving targets. Absolutely nothing can match the speed and accuracy of a laser so they lend themselves to being great weapons for moving targets. My favorite thing in science fiction is the death star, lol (I think the weapons in Star Wars were a little bit more plausible than Star Trek-ie "quantum torpedoes" for one, though they were both far fetched). Ignoring that it takes more energy to do what the death star did than the amount the sun produces per second, the stats are crazy, 2.4E32 Watts and low enough divergence for a range of 6 light seconds. But that's the reason its fiction, so yeah.
The reason I was asking this was because I heard the Navy cut funding for their railgun. Of course the economy is in bad shape but shouldn't they cut down on things that are totally useless to the country, such as the presidents campaign and his and the first lady`s staff? I think they also did the same to the FEL which is a shame as the potential for it is high. I am not saying they should pick one over the other, but along with all the R&D going to lasers, I think they should try doing more stuff with electric gun tech such as railguns/coilguns as the muzzle velocity can be huggee.
 
I think this highly depends on the duration of the laser pulse. If it takes several seconds to deliver this energy, the most likely effects (I'm guessing) would that the laser simply burns through. If all that energy were delivered in about 1 millisecond I think there would be something a akin to an explosion.
 

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