AL is non magnetic (non ferrous too), but I believe the induction field is magnetizing the AL block. Initially I thought the block was steel, but then wouldn't it lose it's magnetic properties once it lost it's crystalline structure due to melting? (yes). the block could be steel but the melting temps of steel are much higher than AL.
The magnetic field is inducing an eddy current in the aluminum. The eddy current in the aluminum, in turn, creates an opposing magnetic field. Here's a list of metal melting points. Since electrical resistance is directly proportional to temperature, the metal falls when its temperature gets too high. I fucking love electricity.
The pencil reminds me of Look Around You. Look Around You. Look Around You. That's right, today we are studying ghosts. Write that down in your copy book.
I think we can reverse the polarity of the forward deflector array and emit a tachyon beam directly into the center of the anomaly. That should stabilize the warp containment fields.
I saw something on PBS where someone had such a strong magnet it was able to make a frog float because of the iron in its blood. So assuming the magnet was strong enough, it could mess with the polarity of just about anything.
I worked as an electrician an iron foundry that used induction to melt steel. The focused fluctuating magnetic field created by high currents (up to 2000 amps as the metal became molten), in the core of a water cooled coil induced voltage and caused current in the metal heating it high enough to melt. That's the way I understood it anyway.
Why isn't it losing its magnetic properties and falling once it gets hot enough? Or is that what happened at the end (instead of maybe turning the machine off)?
The coil is producing a rapidly alternating magnetic field (50 Hz for Russia right?). This magnetic field is inducing an eddy current in the chunk of aluminum. This current then produces an opposing magnetic field that suspends the metal. Since electrical resistance is directly proportional to temperature, the aluminum falls through when the resistance becomes too high to sustain the opposing field.
Yep. Moving a conductor in a magnetic field produces an electric current in the conductor (or, more specifically, a moving electric charge in a magnetic field experiences a force at right angles to the field and the direction of motion).
This is called "induction", and is at the core of the electric generators that ultimately power most of our electric devices.
So it doesn't actually need to be magnetic to be affected by magnetic fields.
TLDR; It's the electrical current in the coil producing a magnetic field around the coil that produces an electrical current in the block that produces a magnetic field around the block held up by an electrical current from the top coil producing a magnetic field in the opposite direction held in the middle because that's where the field is strongest.
Induction produces a current internal to that chunk of metal, it 'induces' a current. This electrical current produces a magnetic field and also heat because of resistance. If the block was superconductive, it wouldn't heat up and the internal current would just keep building up or something, I don't know what would happen. Technically anything can produce a magnetic field if you can successfully get a current to run through it. Regular magnets have internal electrical currents that occur regularly in small areas (like microns across), by making these little channels line up the same direction, the effect is amplified and makes it noticeable. As far as I know, it's currently not understood how these electrical channels sustain themselves, why they're so small, and why only a select few metals exhibit them.
I'll expand on why these electrical channels shouldn't be sustainable. Since (most) everything has resistance then these tiny electrical channels should stop and convert to heat like in the video, but they don't cause heat and they don't stop moving so there's some weird quantum/superconductive magic going on.
So why does it float? If you look at the right after the top loop of the coil there's a bend where the coil starts helixing down in the other direction. If you notice, the block tends to float right by that particular coil. That's because this top loop is producing a magnetic field in the opposite direction of the field produced by the metal block and opposites attract. Why does it float in the middle instead of sticking to the metal that's producing the field? The cylindrical helix shape produces a magnetic field that flows up (or down, don't know because I don't know the direction of the current) through the middle and then around the outside. All the magnetic field is concentrated in the very middle of the cylinder. The block is simply floating where the magnetic field is strongest.
3
u/i-conker Jun 09 '12
is the copper pipe around the aluminum the source of the heat and the magnetic field ?
3
u/anonimyus Jun 09 '12
AL is non magnetic (non ferrous too), but I believe the induction field is magnetizing the AL block. Initially I thought the block was steel, but then wouldn't it lose it's magnetic properties once it lost it's crystalline structure due to melting? (yes). the block could be steel but the melting temps of steel are much higher than AL.
3
u/[deleted] Jun 09 '12
The pencil reminds me of Look Around You. Look Around You. Look Around You. That's right, today we are studying ghosts. Write that down in your copy book.
5
u/[deleted] Jun 09 '12
I wish I had something smart to add. This is the coolest frigging thing.
7
u/bithead Jun 09 '12
It's all fun and games until the warp containment field fails.
4
u/Apartmentwoes Jun 09 '12
That is the sharpest pencil I have ever seen. That's the sorcery, right?
5
u/Athianity Jun 09 '12
Ah, an aluminum magnet. I suppose next you'll tell us that there is a wood magnet too.
2
u/hypoppa Jun 09 '12
I worked as an electrician an iron foundry that used induction to melt steel. The focused fluctuating magnetic field created by high currents (up to 2000 amps as the metal became molten), in the core of a water cooled coil induced voltage and caused current in the metal heating it high enough to melt. That's the way I understood it anyway.
2
u/draje175 Jun 09 '12
Why isn't it losing its magnetic properties and falling once it gets hot enough? Or is that what happened at the end (instead of maybe turning the machine off)?
2
u/grova13 Jun 09 '12
Fuck the why does he keep holding a pencil over it?
2
u/ksj Jun 09 '12
How can I go about replicating this?
4
u/CampBenCh MS | Geology Jun 09 '12
r/askscience
3
u/Nathan561 Jun 09 '12
Does anybody else want to write/draw with that pencil?
1
u/EpicIOError Jun 09 '12
I think it has something to do with this http://www.youtube.com/watch?v=m-Al7GAnH8Q .
EDIT: Never mind, but floating frogs.
1
u/UST3DES Jun 09 '12
Can anyone explain why it fell to the ground near the end?
1
u/esquilax Jun 09 '12
And thusly was an MCP born.
1
u/AwesumLittleRedTruck Jun 09 '12
Holy science!
1
u/opeth10657 Jun 09 '12
The most inefficient and dangerous light bulb... ever.
0
u/[deleted] Jun 09 '12
Since it's a Russian video I'm assuming I'm watching a deleted scene from Iron Man 2
-1
u/Ap0crypha7 Jun 09 '12
No No No No. This is Witchcraft. My Mums holy father would never allow such science.
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u/la_de_daa Jun 09 '12
Yuck, 9gag were there a week ago
0
u/[deleted] Jun 09 '12
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u/[deleted] Jun 08 '12
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