Really Stupid Numbers
I have a friend I consult with on the science behind Arsenal. I’ve said before not all of it is real, but I try to keep it grounded. One of the weapons I’m considering for Inescapable is a mass driver. I’ll save the codename of the weapon for when you read the book. Suffice to say if you’re a fan of 80’s cartoons you will get it.
I pulled a number out of my hat for what I wanted and then ran those numbers by him. His reply follows. He has a good sense of humor and I laughed while reading his post.
Enjoy,
-Jeffery
"No, really... these are dumb numbers, they don't even make sense from a human perspective.
OK, 24oz (.68 kg) of tungsten is a sphere .78 inches (20mm) across. Heavy, but not too big.
To keep it simple, the slug accelerates from rest (0 meters per second) to .03c (8,993,773.74 meters per second) in the space of 1 meter.
This is where it gets seriously stupid. Accelerating 24oz of anything to .03c requires 13,758,820,589,375 (13 trillion) joules of energy, assuming zero loss.
This is 416,934 times more power than the current US Navy railgun uses (33 million joules). So, say there's some loss of energy, and her railgun is five hundred thousand times more powerful than the current real-world gun.
The slug spends 111 nanoseconds on the rails, that's 111 billionths of a second.
Tungsten has a heat of vaporization of 774 kJ/mol, and 24oz of tungsten is 3.7mol.
3.7mol x 774,000 joules = 2,863,800 joules required to vaporize the slug... That's a bit less than 3 million joules... we just pumped 13 trillion joules into that slug. This is four and third million times more energy than is required.
Even if the conversion of electrical energy to kinetic energy is 99.999994% efficient, that slug is still a tight ovoid of tungsten plasma traveling at .03c
It's also glowing white-hot and much brighter than the sun.
The sound it produces is beyond my capacity to calculate... but here are a couple useful approximations of the impact it has.
The ISS in orbit has a bit less mass/energy than the tungsten slug/plasma ball... imagine what that would sound like if it passed you on the freeway.
The Little Boy dropped on Hiroshima has about four times the total energy of the tungsten slug/plasma ball... so, it's like 1/4 as loud as whatever those poor shadow people would have heard if their eardrums hadn't been vaporized before they had a chance to respond to the sound?
A normal person standing 100 feet away would be smashed into a fine paste by the sound of the slug passing.
The fine paste would be cooked to fine carbon powder by the heat radiating off the slug/plasma ball
The air itself cannot get out of the way fast enough, and the atomic nuclei fuse as the slug/plasma ball smashes into them. This slows down the shot just a bit, but also creates about as much heat/light/radiation as the slug itself... but with the added 'benefit' of hard radiation (a gamma/alpha particle 'flash' about equal to sunbathing in an x-ray booth... so the drifting carbon powder is now irradiated.
All of those things would happen in the five-thousandth of a second it took the plasma ball to travel a mile beyond the muzzle of her railgun.
In case you need to know, her ZPFM has to produce 123,953,338,640,000,000,000 watts to accomplish this feat... This is one-third of the total energy produced by the Sun in that same 111 nanosecond time frame.
Stupid, stupid numbers. There's no capacitor or conductive material on earth that could withstand the energy flux. A perfect super-conductive electrical transport system would burn out after one shot.
When the slug/plasma ball leaves the barrel of the railgun, the rails and most of the rest of the gun comes with it as a cloud of slightly cooler plasma wafting along in its wake.
Oh yeah... the radiant flare of heat pouring off the slug/plasma ball will also vaporize her suit... so she needs a very high SPF sunblock.
I won't even go into what happens when all that energy hits an immovable object.
Ain't physics grand?
I pulled a number out of my hat for what I wanted and then ran those numbers by him. His reply follows. He has a good sense of humor and I laughed while reading his post.
Enjoy,
-Jeffery
"No, really... these are dumb numbers, they don't even make sense from a human perspective.
OK, 24oz (.68 kg) of tungsten is a sphere .78 inches (20mm) across. Heavy, but not too big.
To keep it simple, the slug accelerates from rest (0 meters per second) to .03c (8,993,773.74 meters per second) in the space of 1 meter.
This is where it gets seriously stupid. Accelerating 24oz of anything to .03c requires 13,758,820,589,375 (13 trillion) joules of energy, assuming zero loss.
This is 416,934 times more power than the current US Navy railgun uses (33 million joules). So, say there's some loss of energy, and her railgun is five hundred thousand times more powerful than the current real-world gun.
The slug spends 111 nanoseconds on the rails, that's 111 billionths of a second.
Tungsten has a heat of vaporization of 774 kJ/mol, and 24oz of tungsten is 3.7mol.
3.7mol x 774,000 joules = 2,863,800 joules required to vaporize the slug... That's a bit less than 3 million joules... we just pumped 13 trillion joules into that slug. This is four and third million times more energy than is required.
Even if the conversion of electrical energy to kinetic energy is 99.999994% efficient, that slug is still a tight ovoid of tungsten plasma traveling at .03c
It's also glowing white-hot and much brighter than the sun.
The sound it produces is beyond my capacity to calculate... but here are a couple useful approximations of the impact it has.
The ISS in orbit has a bit less mass/energy than the tungsten slug/plasma ball... imagine what that would sound like if it passed you on the freeway.
The Little Boy dropped on Hiroshima has about four times the total energy of the tungsten slug/plasma ball... so, it's like 1/4 as loud as whatever those poor shadow people would have heard if their eardrums hadn't been vaporized before they had a chance to respond to the sound?
A normal person standing 100 feet away would be smashed into a fine paste by the sound of the slug passing.
The fine paste would be cooked to fine carbon powder by the heat radiating off the slug/plasma ball
The air itself cannot get out of the way fast enough, and the atomic nuclei fuse as the slug/plasma ball smashes into them. This slows down the shot just a bit, but also creates about as much heat/light/radiation as the slug itself... but with the added 'benefit' of hard radiation (a gamma/alpha particle 'flash' about equal to sunbathing in an x-ray booth... so the drifting carbon powder is now irradiated.
All of those things would happen in the five-thousandth of a second it took the plasma ball to travel a mile beyond the muzzle of her railgun.
In case you need to know, her ZPFM has to produce 123,953,338,640,000,000,000 watts to accomplish this feat... This is one-third of the total energy produced by the Sun in that same 111 nanosecond time frame.
Stupid, stupid numbers. There's no capacitor or conductive material on earth that could withstand the energy flux. A perfect super-conductive electrical transport system would burn out after one shot.
When the slug/plasma ball leaves the barrel of the railgun, the rails and most of the rest of the gun comes with it as a cloud of slightly cooler plasma wafting along in its wake.
Oh yeah... the radiant flare of heat pouring off the slug/plasma ball will also vaporize her suit... so she needs a very high SPF sunblock.
I won't even go into what happens when all that energy hits an immovable object.
Ain't physics grand?
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My railgun type weapon fires basically athick needle like bullets of tungsten carbide.
Such bullets should be good up to and a little past 2500 Celsius before heat becomes a real problem for them, though they are hot as hell when they hit and will go through most things like a hot knife through butter.
The question is how fast can they be fired and not use insane energy levels (hence the wish to calculate stuff my self). I know that any fractions of light is not reachable and was aiming for a 2-3 times the speed of sound as top speed and ability to be adjusted down for more everyday use. And what is the limits of the material. it bugs me actually that I don't know.
But basically any speed where the tungsten carbide meddles gets close to 2500 C turns it into a terrifying weapon... so getting the max speed in the ball park area would be fine.
Love your books by the way, they are fun