National High Magnetic Field Laboratory(nationalmaglab.org)
nationalmaglab.org
National High Magnetic Field Laboratory
https://nationalmaglab.org/
36 comments
> the nail would reach escape velocity and never come back down to earth
See https://en.wikipedia.org/wiki/Impact_depth
I am not a physicist, but iron is about 6500 times denser than air so that suggests that a 5 cm nail would reach a height of very roughly about 300 metres, assuming you fired it upwards with sufficient speed, it remained parallel to the direction of flight, and it didn't melt or burn.
You should definitely allow more space that that if you're thinking about filming the experiment from a helicopter over your magnet lab, but I would guess that even Nine Inch Nails wouldn't be hitting any satellites.
EDIT: OK, that impact depth formula is only applicable to projectiles travelling faster than the speed of sound in the medium, which is about 300 m/s. But without air resistance an object fired upwards at 300 m/s reaches a height of about 4500 metres! There's a big gap between those two rough approximations, so if someone wants a more accurate answer I suppose they will just have to look up the actual formulae for actual air resistance.
See https://en.wikipedia.org/wiki/Impact_depth
I am not a physicist, but iron is about 6500 times denser than air so that suggests that a 5 cm nail would reach a height of very roughly about 300 metres, assuming you fired it upwards with sufficient speed, it remained parallel to the direction of flight, and it didn't melt or burn.
You should definitely allow more space that that if you're thinking about filming the experiment from a helicopter over your magnet lab, but I would guess that even Nine Inch Nails wouldn't be hitting any satellites.
EDIT: OK, that impact depth formula is only applicable to projectiles travelling faster than the speed of sound in the medium, which is about 300 m/s. But without air resistance an object fired upwards at 300 m/s reaches a height of about 4500 metres! There's a big gap between those two rough approximations, so if someone wants a more accurate answer I suppose they will just have to look up the actual formulae for actual air resistance.
Interesting point. Although, a 5cm nail is tiny, that's like what you'd use to hang a picture on the wall.
A real carpenter's nail is what I was picturing and that's more like 10-15cm which 2-3x's your impact depth (which is still only ~1km).
So I think if anything, your point is basically proof that a nail or any traditional gauss gun projectile would absolutely ablate into gas immediately when fired at the hypersonic speed of orbital escape velocity.
A real carpenter's nail is what I was picturing and that's more like 10-15cm which 2-3x's your impact depth (which is still only ~1km).
So I think if anything, your point is basically proof that a nail or any traditional gauss gun projectile would absolutely ablate into gas immediately when fired at the hypersonic speed of orbital escape velocity.
Yeah, that's why the "rod's from god" idea for an orbit to ground kinetic weapon (which is the same problem just in reverse) used tungsten rods the size of telephone poles, and even those would slow down by 5 km/s as they pass through the atmosphere.
> Every professor had a pitch for why his research was the most exciting but the lab I spent the most time with told me “when I was your age I also went shopping for labs like you are and one of the professors told me he was studying quantum magnetism. So I thought to myself ‘that sounds like something that could impress girls at bars’ so I went to work there.” That reasoning made a lot of sense to me so I signed up for his lab right there and then.
This is fine for undergraduate research assistants since it's unreasonable to expect an undergrad to be able to judge a research program on its merits and you're expected to switch labs in the future anyway. It's much more concerning that graduate students usually select research labs without being able to assess the basic scientific case on the merits. The issue is that once you pick your PhD topic, it's logistically very hard to change research focus more than slightly for the rest of your career. So research programs can get perpetuated across multiple generations even if no well-informed student would start down that path.
This is fine for undergraduate research assistants since it's unreasonable to expect an undergrad to be able to judge a research program on its merits and you're expected to switch labs in the future anyway. It's much more concerning that graduate students usually select research labs without being able to assess the basic scientific case on the merits. The issue is that once you pick your PhD topic, it's logistically very hard to change research focus more than slightly for the rest of your career. So research programs can get perpetuated across multiple generations even if no well-informed student would start down that path.
Though it's very important to get a supervisor you can collaborate with, especially for your mental health, so choosing mainly based on personal chemistry is a valid strategy.
This is a great story, thanks for sharing. I'm a chemistry graduate and also had fun sweeping the dusty chem lab floor with liquid n2! ;P ;) xx
Can you say more about using LN2 to clean dusty floors? Asking for a friend.
Imagine pouring a bunch of water on the floor that picks up and carries the dust some distance, then 2 seconds later the water is gone and the dust is deposited in its new location.
It's fantastically effective for carrying crud out from under difficult-to-move equipment, to somewhere you can easily sweep it up.
It's fantastically effective for carrying crud out from under difficult-to-move equipment, to somewhere you can easily sweep it up.
This. It carries the dust to the walls and then you just sweep the edges. Just sweep it on the floor and watch it work.
My wife manages science labs. People can't ride in an elevator with LN2 for fear of displacing all oxygen.
I imagine pouring it across the floor had to be careful in some sense! (IE not too much, well ventilated, make sure no one who cares - like lab managers - are around...)
I imagine pouring it across the floor had to be careful in some sense! (IE not too much, well ventilated, make sure no one who cares - like lab managers - are around...)
Yeah, picking it up from the supplier, they _really_ want you to be in a pickup truck so it can ride outside.
I was able to placate with "The place I'm going to is literally around the block, like half a mile from here, I could walk the dewar there and then walk back for my car if that's better, but honestly I'm just gonna drive with all the windows down", and they grumbled but they did let me leave.
I should get a hitch-mount carrier...
I was able to placate with "The place I'm going to is literally around the block, like half a mile from here, I could walk the dewar there and then walk back for my car if that's better, but honestly I'm just gonna drive with all the windows down", and they grumbled but they did let me leave.
I should get a hitch-mount carrier...
We should pursue this as a launch system. Anything not affected by high G’s could work. Raw materials, maybe fuel.
It's not a very ideal launch system. Not only must your payload contend with high accelerations, but also a huge pulsed magnetic field. This will make launching electronics more difficult, because they will be exposed to a large electromagnetic pulse.
Rail guns are under active development. Also, escape velocity is not practical in that is doesn't account for atmosphere.
That and acceleration at launch will kill most cargo.
> The professor told me that if he put the magnet down with the axis in the vertical direction and pulsed it with an iron nail standing under the magnet that the nail would reach escape velocity and never come back down to earth
Hmm that sounds suspiciously like the descriptions of the systems that are rumored to operate and power UFO’s. Research “electrogravitics”.
Hmm that sounds suspiciously like the descriptions of the systems that are rumored to operate and power UFO’s. Research “electrogravitics”.
To all those downvoting. Do your due diligence first like I did ;)
Coil up some wire and run electricity through it, you get a magnetic field which can pull magnetic materials. That's an electromagnet, e.g. used in door locking systems, and lifting cars into car crushers. Instead of pulling on a car, fix some magnetic material to an axle and a ring of coils around it, the magnetic pulls make the axle turn, you have an electric motor.
Have some freely moving magnetic material, and unroll the motor into a line of coils, and you can make a linear motor as used in a maglev train. Make the electric current pulses powerful enough, and the thing is fired away very fast, your linear motor becomes a rail gun.
Make a huge pulse and make the thing small and light, and it could go fast enough to reach escape velocity from one coil. Handwavy estimates: An 8d nail weighs around 5 grams[1], it takes 28kWh to get 1kg past escape velocity[2], so about 150Wh into the nail might do it. Pump about 2 laptop batteries worth of energy into accelerating the nail between the moment it picks up off the ground, and the moment it exits the top of the coil travelling at several kilometers per sec - that's going to need a big setup with supercooling and high power capacitors because the time window is so short, not because it's using secret alien technology.
It doesn't sound "suspiciously like gravity manipulation" at all?
[1] at ~100 8d nails to the pound, and ~450grams to the pound, 1/100th of 450 makes 4.5grams, rounded up: https://www.treeisland.com/sites/default/files/documents/bro...
[2] https://space.stackexchange.com/questions/4330/how-much-ener...
Have some freely moving magnetic material, and unroll the motor into a line of coils, and you can make a linear motor as used in a maglev train. Make the electric current pulses powerful enough, and the thing is fired away very fast, your linear motor becomes a rail gun.
Make a huge pulse and make the thing small and light, and it could go fast enough to reach escape velocity from one coil. Handwavy estimates: An 8d nail weighs around 5 grams[1], it takes 28kWh to get 1kg past escape velocity[2], so about 150Wh into the nail might do it. Pump about 2 laptop batteries worth of energy into accelerating the nail between the moment it picks up off the ground, and the moment it exits the top of the coil travelling at several kilometers per sec - that's going to need a big setup with supercooling and high power capacitors because the time window is so short, not because it's using secret alien technology.
It doesn't sound "suspiciously like gravity manipulation" at all?
[1] at ~100 8d nails to the pound, and ~450grams to the pound, 1/100th of 450 makes 4.5grams, rounded up: https://www.treeisland.com/sites/default/files/documents/bro...
[2] https://space.stackexchange.com/questions/4330/how-much-ener...
>It doesn't sound "suspiciously like gravity manipulation" at all?
Try adding some rotary effects and then it may. You gotta think outside the globe.
Try adding some rotary effects and then it may. You gotta think outside the globe.
Could you, like, give some actual detail, instead of making us try to guess what you have in mind? Because we're bored of that game...
sure not a problem. Parse through this document : https://patentimages.storage.googleapis.com/0e/5e/e0/eb08a31...
Ah, Biefeld-Brown effect: https://en.wikipedia.org/wiki/Biefeld–Brown_effect
Yes. What about it? It’s interesting isn’t it?
You started off talking about how a supercooled electromagnet sounds like a theorised UFO operating mechanism which involves electrogravitics. When pushed, you suggested rotation was involved. When pushed again, you linked to a patent which presumably was related to your statements, but instead it describes an atmospheric electricity harvesting pyramid. It insists the device must be pyramid shaped and not boxy, and that the pyramid must be big - 150m high and with a 40,000 square metre base. The shape is important for the described effect to happen, and the size is important to have enough voltage difference between base and peak. NB. this thing is HUGE, the base is the area of a soccer pitch, and the height is more than 3x higher than the Hindenburg, the biggest flying machine ever built. [Aside, it's claimed that the pyramid will have a 30kV potential difference between base and peak; how come I don't get electrocuted when I stand up if the 200V/meter potential gradient near the surface of the Earth claim is correct? How come we don't get this power generation at all from 600m high asymmetric skyscrapers with steel superstructures?]. This pyramid will harvest atmospheric / thunderstorm electricity and be a power supply for civilization. The patent then moves on to describing a vehicle with a spehrical capacitor small enough to go in a vehicle and a rod sticking out the top which must be positively charged, with no explanation where the pyramid or the massive size requirements went, or how or why the capacitor will do anything of any interest. Is it really suggesting "put a rod in the air and electricity will flow"? Because a) yes that happens, they're called aerials and they put out small amounts of electric signals and they don't take off, and b) wouldn't that happen with lightning conductors on buildings, and they be used as power supplies?. Still, put that aside and see how the patent describes the mechanism of operation:
There exists a MagnetoHydroDynamic drive, it's able to push seawater using only electricity and no other moving parts, and there is a ship called Yamato 1 built to experiment with it: https://en.wikipedia.org/wiki/Magnetohydrodynamic_drive that's cool. There exists a small airplane built by MIT which uses high voltage wires and no moving parts to generate an ionic wind to lift itself: https://news.mit.edu/2018/first-ionic-wind-plane-no-moving-p... that's cool. Biefeld-Brown lifters are interesting.
Connection to UFOs, antigravity, or the experiment with the nail described in this thread, still not apparent.
"When all capacitor plates are charged, a pressure differential is
induced and above the craft the pressure will be higher than
at the bottom of the craft. This pressure differential is
unstable and progresses towards an equilibrium. It will
propel the craft forward in order to eliminate the pressure
gradient."
There exists a MagnetoHydroDynamic drive, it's able to push seawater using only electricity and no other moving parts, and there is a ship called Yamato 1 built to experiment with it: https://en.wikipedia.org/wiki/Magnetohydrodynamic_drive that's cool. There exists a small airplane built by MIT which uses high voltage wires and no moving parts to generate an ionic wind to lift itself: https://news.mit.edu/2018/first-ionic-wind-plane-no-moving-p... that's cool. Biefeld-Brown lifters are interesting.
Connection to UFOs, antigravity, or the experiment with the nail described in this thread, still not apparent.
> Connection to UFOs, antigravity, or the experiment with the nail described in this thread, still not apparent.
And yet much of it remains unapparent including how the effect you described “air flowing over a wing” makes a jet stay in the air: https://www.scientificamerican.com/article/no-one-can-explai...
The point is there is only so much data open source and it is interesting to extrapolate what electromagnetism means to gravity because there might be a connection there. Whether it’s a school project to make a nail rocket into space or making a lifter with no moving parts. Putting it out to a thread dealing with electrical magnetic work is the right idea to get us thinking in this direction to discuss and discover what might be possible in these emerging areas.
And yet much of it remains unapparent including how the effect you described “air flowing over a wing” makes a jet stay in the air: https://www.scientificamerican.com/article/no-one-can-explai...
The point is there is only so much data open source and it is interesting to extrapolate what electromagnetism means to gravity because there might be a connection there. Whether it’s a school project to make a nail rocket into space or making a lifter with no moving parts. Putting it out to a thread dealing with electrical magnetic work is the right idea to get us thinking in this direction to discuss and discover what might be possible in these emerging areas.
> "what electromagnetism means to gravity because there might be a connection there"
Skim-read this: https://www.lesswrong.com/tag/privileging-the-hypothesis and then what evidence are you using that there "might there be a connection there"? Your "air flowing over a wing" link at least has a hundred years and many millions of flying hours showing that wings must work in some way related to air.
Skim-read this: https://www.lesswrong.com/tag/privileging-the-hypothesis and then what evidence are you using that there "might there be a connection there"? Your "air flowing over a wing" link at least has a hundred years and many millions of flying hours showing that wings must work in some way related to air.
Interesting. Granted in December 2005. So in the intervening 15 1/2 years, has someone shown a working device? Can you point me to documentation of that?
Umm I think you just answered your own question.
I'm a little confused why the NHMFL home page ended up in my hacker news RSS feed, but I received my PhD here and thus feel obligated to comment and upvote...
Me too. I did notice another story for the same domain on today's front page of HN.
https://news.ycombinator.com/item?id=27502233
https://news.ycombinator.com/item?id=27502233
Seize the opportunity to talk about what you did there!
i mean nhmfl isn't a degree granting institution so i think you mean you got your phd at fsu
My first development gig in high school was at the NHMFL working with the photo microscopy guys on various projects. It was a great experience that got my development career rolling. This was the mid/late 90's. We went from developing hyper card stacks to OSHA training educational tools and testing in HTML/perl. Good times.
I suspect we met at some point. My friend and I got busted rooting the server at the gifted school (ARC) in ‘97, but instead of calling an authority, the teacher called Mike and we spent the next two years or so playing with SATAN/SANTA, learning Perl and C++, and experimenting with 3D graphics in Java. I can draw a straight line from Logo Writer, through the mag lab, and to my current job.
The second lab where I worked used regular Helium (4 K temps) and only 5 T magnets to perform slow NMR measurements. We had a partnership with the chemistry department and the overall goal of the project was to grow a crystal that was able to become opaque or transparent by using a magnetic field at room temperatures. The idea was that with a crystal like that you could do signal switching for fiber optic networks without having to convert the signal from optical to electric and back, thus greatly increasing network speeds. The effort at the time was 50 years in the making and no solution was discovered yet but it was fun to grow my own crystals and see how they responded to sweeps of the magnetic field, movement in a constant field, and temperature changes. I also got to learn Origin C, a peculiar variant of C used by a statistical package the lab employed, played with a lot of liquid Nitrogen (great for cleaning dusty floors!), programmed a crystal growing box/PID controller, and even though I was only an undergrad, because it was a small department and lab I got to write a thesis and both the physics and chemistry departments gathered to see me present it (I was the only physics grad in my year despite a dozen the year before and after). The crux of the thesis was a new term we called “spin freezing”.
But the best part of the whole thing was when I was picking out the labs. Every professor had a pitch for why his research was the most exciting but the lab I spent the most time with told me “when I was your age I also went shopping for labs like you are and one of the professors told me he was studying quantum magnetism. So I thought to myself ‘that sounds like something that could impress girls at bars’ so I went to work there.” That reasoning made a lot of sense to me so I signed up for his lab right there and then.