magnets melting metal?
magnets melting metal Codys Lab

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I'm still working on the "stopping a bullet with magnets" problem. This test told me the most so far: I know what temperature copper forms the black oxide (though in hindsight an infrared thermometer would have been useful) and I know the heat capacity of copper. assuming minimal radiate losses and assuming that the kinetic energy of the penny/bullet would be converted to heat I can calculate how fast the coin/bullet would have been slowed down by the magnets. Now of course the flywheel isn't going past nearly as fast as a bullet would be but since the force acting on the metal increases asymptotically the difference isn't actually all that great. So given all that it looks like I would need over a kilometer of thees magnets to slow a piece of copper down from 300m/s. I could probably decrease that significantly though by using a double row of magnets, stronger magnets, cooling the bullet to liquid nitrogen temperature, using a lighter conductive material like aluminium or calcium, ect.


Benrob0329 : You're going to try to melt the bullet aren't you?

bexpi : Well that's one way to solder 😂

Cory Ory : How to solder without a soldering iron...

Mik : you basically made an induction heater, right?

ֆהტϣ : Last video: "Melting a penny is illegal" This video: *Melting a penny*

USWaterRockets : Would a strong enough magnetic field be able to melt the copper into liquid or maybe a plasma? This would make a cool explanation for how "energy shields" work on all the TV shows/movies/etc.

Arno nümuss : Nice, you made a mechanical induction furnace :D

SandPox : Wow damn, I didn't even know this was possible

Robert Leitch : Cody made the world's noisiest soldering iron

Drew's Page : My mate Eddy Current seems to be at work here....

Jerry Rupprecht : Looks like Cody’s making a new furnace.

John Possum : A new way to solder. Unfortunately the lister engine/generator is not exactly portable.

Franz Goerlich : Hey Cody I was thinking about grafting a tomato plant to a potato one. Theoretically it should work because the have the similar least worth trying :))

Michiel De Maré : "How did that look?" - "BEAUTIFUL!" 😃 Canyon is awesome!

Daniel Bolan : Hook this up to an exercise bike and you've got a human powered induction heater!

The Darasz : 23°C spinning magnet vs ... memes are comming lol

The Puppet Of Everything : Cody you should try and make a Sterling engine out of something preposterous like a soda can.

Peter Houle : haha literally demonetized

tek413 : Eddy currents are crazy. Thank you magnetic feilds

750 kV : Sounds like a single cyl 4-stroke diesel engine, maybe a vintage one. I'd love to see a vid of it.

Newt : You're really trying to stop a bullet with magnets aren't you Cody?

Steve Feather : Waiting for the crazy techno to drop after intro beat... Thx Cody, always informative. =]

Jacob L : I think you need bigger magnets and a faster spinning wheel ;D

Isaac Westawski : Hey cody did your primary account get temp banned again? What did you do shoot a *bullet* past some magnets? ... did it melt?

Erzgebirge erleben : Long awnser short. Bullet stopping is not going to happen... Nice demo, thanks!

Eric M : Is it an inductive effect ? thx for your videos Cody, cheers from Paris !

MasonP13 : You could try cooling the magnets as well, because they're more efficient when cooled, usually.

naraic0o : "How'd that look?" "Beautiful!" <3

PsychoLucario : liquid nitrogen chilled bullets sound like an exploded bullet

DerFailer : Let's build a stove based on this :) I heard induction heaters are very efficient ;)

69aussieguy : I love the way Cody goes to all the effort to set this up, and then makes a 53 second video with no commentary. I know the video description gives some insight, but still.

Pasu suel : maybe use capacitors and coils for creating a temporary high magnetic field? if a coil gun barrel can propel a bullet rapidly, it should also be able to slow it down rapidly.

Scrap Science : Wow. I didn't think it was that easy to make a motor-driven version of an induction heater. Great Stuff.

Andrew Neal : Wow, you should make a whole video on this. Could make a pretty cool solder pot if the speed of the magnets' polarity alternation can regulate the temperature.

gattabat : I see Cody is progressing towards his primary goal of becoming Magneto. First the magnet implant, now this

ZocXer : why not crank the magnets by hand and on some sort of heavy flywheel so it keeps rotating

swampratt36 : I see an induction furnance bluprint in a cloud above Cody's head !

Martin Dinner : One small problem: The majority of a standard bullet (even military issue FMJ) is lead, not copper! The sad truth is that you could stop it/redirect it faster using compressed air.

DailyToker : I would love to see this concept optimized or perfected. I'm sure you could achieve great results.

Shawn Abernethy : HOORAY FOR EDDY! (currants)

Damon Jackson : I've never even considered mechanical induction! Good work and keep it up

MilkCap : Is electricity hooked up to the magnet?

RWBHere : Remember that friction of the air on the bullet will also affect its temperature and velocity, and that it may already be hot as it leaves the gun, because of the explosive charge. You will not need quite as long a line of magnets as you think. For starters, how much will the projectile's velocity be reduced by per unit distance, and at a given point in its ballistic arc?For instance, if the bullet has a range of 900 metres when fired upwards at a theoretically optimum angle of 45°, then its velocity will be significantly less than the initial 300 metres/second after 300 metres, and it will take longer than 3 seconds to travel 900 metres. The effects of the Earth's gravity will also come into play if you fire the bullet upwards at any angle (as you have to do, unless your target is below the gun) and try to slow it down from a point above the gun. Finally, although the mass of the projectile will determine how much magnetic field you will require, as you no doubt know, but is it actually a solid bullet whilst in flight? Some higher speed, or lower melting point, projectiles (such as lead ones) can melt to a liquid, and solidify again later in flight, during which time they can begin to split into smaller fragments. Your findings should be really interesting, if you can find a viable way of controlling the path and velocity of a bullet. OTOH, it's far simpler to pass the projectile through several spaced-apart metal shields to stop it in a very short distance, as is done with parts of the ISS and smaller space debris. A demonstration of that process would also be really interesting, Cody. (Hint, hint!)

The Dude Abides : Do you think you have enough energy to boil some water in a copper pot spinning the magnets with only pedal power?

Dancing Rain : Are your poles just alternating north-south-north-south, or did you use a Halbach array? In trying to stop a bullet, arranging the magnets as Halbach arrays would increase the field.

stefantrethan : You'll most likely deflect the bullet quite a bit with the magnets, it could be impossible to have it stay close for very long without crashing into them. Took me a second to realize this is the flywheel of the generator, would be nice to see how closely you spaced the magnets.

Austin Randolph : Magnetic induction! The moving magnetic fields induce a current in the metal, which heats it up! I wonder if this effect is exacerbated by the fact that the penny is a combination of zinc and copper.

M Kuehn : excellent description breakdown, by discussing kinetic energy, you bring up a good contrast, breaking it down to essentially a math problem, or solving it with physical experimentation. as nerdy a non video it would be, proving the distance with math makes total sense. the same as your video of drinking organic mercury, i approve! but i did watch the Richard Feynman entropy videos after that one. But a "lighter" conductive material would have the same kinetic energy, just a higher velocity, for the same propellant

Maxx B : Magnetic induction, cool way to demonstrate it. I've only ever seen it done with a static coil. Nice work.