Physic do not apply to sci fi games everyone knows that

Acctualy (ideally) you would not want to use material with a high mass as a rail projectile. Basically the idea behind rail tech is to weaponize velocity itself. In so doing you would want to use a material with an extreme low mass but strong molecular bond. Aluminum or some composit material perhaps. Ideally the target speed you would be attempting to achive would be well in excess of 10^4 miles per second. Mater impacts behave much differently at these speeds. Also you would want to maximize impact surface area, and thus, would be firing a cone shaped projectile (a diamond shape for instance) butt first, in order to maximize impact splash.

{edit>>> As for moveing the tank on impact, this would not happen. As I said mater impacts at these speeds behave much differently. Upon contact, the projectile would instanaiously atomize the target and splash affected areas. At these speeds mater to mater contact behaves more like two bodies of liquid interacting.

Does the 80GJ figure come from an official source? (Do we even have an official wiki yet?)

I'm looking at the in game description of the sniper rifle at the moment and all it says is that it shoots 2-inch, "beehive" flechettes. I know next to nothing about guns, so when the game says "... the sniper rifle effectively weaponizes velocity, putting an inert round downrange in excess of 2500 m/s," I have no idea whether that accounts for, say air resistance. Still, it sounds like you guys don't need to guesstimate a figure for velocity and need only play with mass. Mass that must still sound reasonable for a 2-inch flechette made of whatever material that's light enough to allow a scout to sprint at 7.8 m/s.

If we plug 2.500 m/s into the equation E = 1/2*M*V^2 we get M = 25,600 Kg. So, a fully loaded tactical sniper rifle would weight 768,000 Kg or about as much as 716 Hyndae i20s. Also, each 2-inch flechette would weigh about as much as 24 i20s. That's a lot of mass for a mere 2 inches!

(I'm laughing so hard right now )

Yeah, the 80GJ figure just can't be right x'D

... and lets not even get into how the hell can the scout suit guarantee a 7.8 m/s sprint speed, regardless of the planet's gravitational field. Unless we assume New Eden is strewn with Earth like planets :p

EDIT: I just realized that the OP was talking about the big railgun installations, not the mini-railguns snipers carry around. My bad, but I'm gonna leave the post here in case it makes anybody laugh.



Tell me more about how you are surprised to find nerds in the forums of a sci-fi MMOFPS

Seems to me you're assuming 100% efficient conversion of electrical energy into kinetic. Rarely does that happen.

So unless physics works different in Iceland....

So they are 80 GJ railguns
that is 80,000,000,000 J

Work equals change in energy

80,000,000,000= 1/2 M V^2

assuming the mass of railgun projectile is 100 kg (prolly on the heavy side)

V= 28,284 M/S

Now that makes it from my house in Wisconsin to Iceland roughly 3 min.

That would be enough to orbit almost ANY planet
That hits the 600 m max range in .02 seconds.
If you had a 30 FPS film of the railgun you would not even catch the projectile in 1 frame

The air pressure would be enough to blow clones away

Now lets assume the shield tank weighs about 100 Metric tons
(M1 abrams tank weighs 60 Metric Tons)

Then M1V1= (M1+M2) V2

V2 = v tank
V2 = 31 M/S

That is more than the top speed of the tank, so if it is moving at full speed it will be pushed back at about 10 m/s

So CCP are they really 80GJ railguns?

Even assuming something insane, like a 50% railgun inefficency, just half all the speeds and double the times and it is still outrageous. I lol so bad when i was doing this!

So ya, this is what I do when I don't play Dust

I just think this is were people are drawing the line on physics. Not the drop uplinks creating mini wormholes. Not the inertia dampener. Not the any number of other things that don't really make sense science wise. This a rail gun is the point were people are saying "no, this just doesn't make sense".