The problem is that you cant levitate your object because you need it touching the rail to conduct the drive current.
Thats the main problem. Else you could just throw a bagload of teflon on the slug and fire away.
The main problem is not physical abrasion, but the fact that even if the projectile fits perfectly, the current density creates arc discharges between rail and slug, vaporizing the top layers
Think of metal. You get a carrier density of 10^23 cm^3 with a charge of e =1.602*10^-19 each. so you have around 10000 coulomb per cm^3.
Compared to capacitors, a coulomb is a lot, but in metallic conductors a lot of charge is moving, which results in very low carrier speeds (typically around 1cm/s under normal circumstances).
But with those magnets, you have much higher current densitys and those forces become one of the main problems designing them. They are heavily reenforced with aluminium structures because they would simply fly apart...
Have you any links to papers regarding the sonoluminescense bubbles? I always thought that neither pressure nor temperature does even come close to the needed levels.
btw: The ultimate energy source would be an ultrasmall black whole trapped in a ioffe-trap. Just keep it at a size with significant hawking radiation and feed it with a particle jet. You get 100% mass to energy conversion. (but i thing you also get a small problem with entropy and thermodynamics. they dont really like such stuff:) )
Yeah, but if you realize what such an field gradient would do with the electrons, you would see that that wont stay cool for more than a few plank-times....
Yes, but i was actually amazed as i read that it was in 12000m height. It felt more like "oh the fuck that was close":) Thats only slightly lower than concorde traval hight.
There is a reason why the concorde only went supersonic above water
It is LOUD. Its not like the long fading sound a subsonic jet creates, but a short "hit" of sound, like a gunshot, but with lower frequences. Thing of a bomb detonating 200 meters away or a single bass beat from love-parade class speakers inserted into silence.
A story i cannot verify is that in the early 80s a pair of tornados practives ultra low altitude "vallay crawling" and something went wrong. One pilot needed to gain altitude fast because he left the cloud layer facing a hill slope. He used the afterburner and broke the sonic wall only a few hunderd meters above a village. They hadn't got much unbroken windows after that and the church had suffered cracks a few centimeter wide in its ceiling.
A month ago a F4 went supersonic in 11000m height in the area i live. Actually, it traveled 200km west to east through north bavaria. I can tell you "boom" is a light understatement...
I grew up near an infantry test area and im quite used to RPG explosions in the distance ect.
I was standing near an open window and could feel the pressure. It was like back in the army if someone detonated a practice handgranate and your earplugs filter out the high frequency noise.
I read in the paper the next day that hundereds of people called the police believing there was some kind of bombing...
Yeah, it would. But you have to take into account the mass of jupiter. Even if he has only a 1% of the uranium density of the earth, it still translates to a giant amount.
Yeah, that too. But i dont think you can direct all blame to one reason.
Sure, they shouldnt be able to get their hands on guns(believe me, the american guncrazyness is something that makes be disbelieve they are already in the 21th century) But they also shoulnd be thaught that taking potshots at cars is cool. Hey, i wasnt influenced back in my youth, so i just made "geological experiments" by creating blast craters in my grandfathers potato field. Some kids i met the last years cry about how games dont frag anymore (they only drop death and there is some blood. I WANT PEOPLE TO BLOW UP TO PIECES! THATS THE BEST PART!!!). No kidding. Including caps.
Yeah, i feel the same. But the differenes is that as a teen i was stupid enough to really do stupid things, and now i only think about it but dont to it.
THATS why some stuff should be kept from immature people.
Well, there wont be any plutonium because plutonium has no isotope with 10^8 year decay time. everything is already decayed. But im totally positive that there are billions of tons of uranium in jupiter....
Well, think big: With this device your mp3 player and camera dont need more than a little ram anymore, so you can integrate the mp3 player into the earphones. Your digital camera can now be included in you cell phone, which has bluetooth already, and sends it pictures to the server. Considering the fact that the server has a processor, your pda can be a dumb client, so you could just integrate a hud in your glasses and a wireless keyboard for input.
I think it is quite useful to concentrage storage space and processing power in one place.
Are you really trying to say higher video bit rate is a bad thing? If i buy a really expensive ultra high capacity dvr, i dont want to watch moving macroblocks. Heck, why dont you just record CIF-mpeg1? Then you would get 2h per Gb, which would make it a better device the way you argue...
Do you really have such a bad network? I have a gsm phone here in germany since 97 and never witnessed a disconnect besides obvious things (driving into a tunnel).
And you add cameras to phones because people like to carry cameras aound to make snapshots of interesting things. And they also carry cell phones around. both are digital devices with a case, battery, display, processor, memory, ect. So people who want both need only one gadget in the pocket, and everybody else can buy a phone without a camera.
Actually, a cell phone and a digital camera are two decives that are really GREAT to combine. The whole reason for small cameras is making snapshots ect. Therefore you need the have them around when something happens that you want to make a photo of. Now on the otherhand, most people own a cell phone, and they naturally have it with them. Now both devices need a signal processor, an accu-pack, memory, ect. So it is quite sensible to make them one device.
the word mile derives from "milum passum" (sorry, my latin died years ago), the lenght of 1000 double steps (meaning 1000 times the lenght from left foot down to left food down...)
To be fair, i havent seen any program that was not somehow hw-related(dx-release, video-card driver) that needed a windows restart. Not in xp, not in 2000, not even in 98. Its just that many versions of installshield had these "Restart after finish" option everybody used. A click on cancel and then starting the program hasnt ever failed.
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The problem is that you cant levitate your object because you need it touching the rail to conduct the drive current.
Thats the main problem. Else you could just throw a bagload of teflon on the slug and fire away.
The main problem is not physical abrasion, but the fact that even if the projectile fits perfectly, the current density creates arc discharges between rail and slug, vaporizing the top layers
Think of metal.
You get a carrier density of 10^23 cm^3 with a charge of e =1.602*10^-19 each.
so you have around 10000 coulomb per cm^3.
Compared to capacitors, a coulomb is a lot, but in metallic conductors a lot of charge is moving, which results in very low carrier speeds (typically around 1cm/s under normal circumstances).
But with those magnets, you have much higher current densitys and those forces become one of the main problems designing them. They are heavily reenforced with aluminium structures because they would simply fly apart...
I guess better than you speak german.
Have you any links to papers regarding the sonoluminescense bubbles?
:) )
I always thought that neither pressure nor temperature does even come close to the needed levels.
btw: The ultimate energy source would be an ultrasmall black whole trapped in a ioffe-trap.
Just keep it at a size with significant hawking radiation and feed it with a particle jet.
You get 100% mass to energy conversion.
(but i thing you also get a small problem with entropy and thermodynamics. they dont really like such stuff
Yeah, but if you realize what such an field gradient would do with the electrons, you would see that that wont stay cool for more than a few plank-times....
Yes, but i was actually amazed as i read that it was in 12000m height. It felt more like "oh the fuck that was close" :)
Thats only slightly lower than concorde traval hight.
There is a reason why the concorde only went supersonic above water
http://science.slashdot.org/comments.pl?sid=77565& cid=6895042
It is LOUD. Its not like the long fading sound a subsonic jet creates, but a short "hit" of sound, like a gunshot, but with lower frequences.
Thing of a bomb detonating 200 meters away or a single bass beat from love-parade class speakers inserted into silence.
A story i cannot verify is that in the early 80s a pair of tornados practives ultra low altitude "vallay crawling" and something went wrong.
One pilot needed to gain altitude fast because he left the cloud layer facing a hill slope.
He used the afterburner and broke the sonic wall only a few hunderd meters above a village.
They hadn't got much unbroken windows after that and the church had suffered cracks a few centimeter wide in its ceiling.
A month ago a F4 went supersonic in 11000m height in the area i live. Actually, it traveled 200km west to east through north bavaria.
I can tell you "boom" is a light understatement...
I grew up near an infantry test area and im quite used to RPG explosions in the distance ect.
I was standing near an open window and could feel the pressure. It was like back in the army if someone detonated a practice handgranate and your earplugs filter out the high frequency noise.
I read in the paper the next day that hundereds of people called the police believing there was some kind of bombing...
Yeah, it would. But you have to take into account the mass of jupiter. Even if he has only a 1% of the uranium density of the earth, it still translates to a giant amount.
Yeah, that too. But i dont think you can direct all blame to one reason.
Sure, they shouldnt be able to get their hands on guns(believe me, the american guncrazyness is something that makes be disbelieve they are already in the 21th century)
But they also shoulnd be thaught that taking potshots at cars is cool. Hey, i wasnt influenced back in my youth, so i just made "geological experiments" by creating blast craters in my grandfathers potato field. Some kids i met the last years cry about how games dont frag anymore (they only drop death and there is some blood. I WANT PEOPLE TO BLOW UP TO PIECES! THATS THE BEST PART!!!). No kidding. Including caps.
Thats something really disturbing, imho.
Yeah, i feel the same. But the differenes is that as a teen i was stupid enough to really do stupid things, and now i only think about it but dont to it.
THATS why some stuff should be kept from immature people.
Well, jar jar must die, because he isnt there in episode 4.
My dream scene of episode 3 is yoda facing jar jar before going to dagobar:
"For passing the law making palpatine emperor, suffer you will!" -> zaaaappppp.....
Thats called blades :)
tell me what moving part a mouse has? The photons from its LED? or the electrons in its ICs?
Well, there wont be any plutonium because plutonium has no isotope with 10^8 year decay time. everything is already decayed.
But im totally positive that there are billions of tons of uranium in jupiter....
Well, think big:
With this device your mp3 player and camera dont need more than a little ram anymore, so you can integrate the mp3 player into the earphones.
Your digital camera can now be included in you cell phone, which has bluetooth already, and sends it pictures to the server.
Considering the fact that the server has a processor, your pda can be a dumb client, so you could just integrate a hud in your glasses and a wireless keyboard for input.
I think it is quite useful to concentrage storage space and processing power in one place.
Are you really trying to say higher video bit rate is a bad thing?
If i buy a really expensive ultra high capacity dvr, i dont want to watch moving macroblocks.
Heck, why dont you just record CIF-mpeg1? Then you would get 2h per Gb, which would make it a better device the way you argue...
Do you really have such a bad network? I have a gsm phone here in germany since 97 and never witnessed a disconnect besides obvious things (driving into a tunnel).
And you add cameras to phones because people like to carry cameras aound to make snapshots of interesting things. And they also carry cell phones around. both are digital devices with a case, battery, display, processor, memory, ect.
So people who want both need only one gadget in the pocket, and everybody else can buy a phone without a camera.
Actually, a cell phone and a digital camera are two decives that are really GREAT to combine.
The whole reason for small cameras is making snapshots ect. Therefore you need the have them around when something happens that you want to make a photo of.
Now on the otherhand, most people own a cell phone, and they naturally have it with them.
Now both devices need a signal processor, an accu-pack, memory, ect.
So it is quite sensible to make them one device.
Hehe. Im already there. Theres some reason its called the internet, you know....
yeah, 40km hight means around 1*e^-(40/4.5)bar pressure. They cant shit out of their basket because its near vaccum out there....
the word mile derives from "milum passum" (sorry, my latin died years ago), the lenght of 1000 double steps (meaning 1000 times the lenght from left foot down to left food down...)
I normaly dont reply to myself, but i have to say that i think it is REALLY disturbing that my post was modded +1 informative.
People use units that arent derived from bodyparts or the lenght of 1000 steps....
To be fair, i havent seen any program that was not somehow hw-related(dx-release, video-card driver) that needed a windows restart. Not in xp, not in 2000, not even in 98.
Its just that many versions of installshield had these "Restart after finish" option everybody used. A click on cancel and then starting the program hasnt ever failed.