Levitating Barbecue! Electromagnetic Induction

At the Palais de la Decouverte in Paris, they showed me this experiment where a 1kg aluminium plate is levitated above a large coil of wire that is being supplied with 800A of alternating current at 900Hz. This is by far the best demonstration of electromagnetic induction I have ever seen.

Back in London, I visited the magnetic lab of Michael Faraday in the basement of the Royal Institution. It was here that he did his groundbreaking work on induction. People had previously observed that current in a wire causes a compass needle to deflect, but more exciting was the prospect of using a magnetic field to generate current. Faraday created his famous induction ring by winding two coils of insulated wire onto an iron ring. When he connected a battery to one coil, a small pulse of current was induced in the other. When the battery was disconnected, current was induced in the other direction. This led Faraday to the conclusion that current was induced in the second coil only when the magnetic field through it was changing.

And if they hadn't been wrapped on the same ring, Faraday may have noticed that the two coils repel each other when the current is induced due to the interaction of their magnetic fields. This is the same thing that is happening with the aluminium plate, except we're using alternating current to create a continually changing magnetic field. This induces an alternating current in the plate, producing an opposing magnetic field which levitates the disk.

[Mike-hnxg]

Guy: "Don't put the lamp too close"
Derek: Immediately tries putting the lamp directly on it.

[NicklausSIR]

You didn't mention the elctricity bill of this device, though.

[Rasecz]

Had a trip to Paris this week to meet a friend, took some time apart to go to this place 'Palais de la Decouvet', saw all the electromagnetism demonstrations they do, not only this one, and many other interesting experiments in other areas of physics. The whole experience was amazing. Wouldn't have known about this place if it wasn't for you. I sincerely thank you for that.

[DaylightDigital]

Who needs magic when you've got Physics?

[Garbage]

So interesting please remake this video I want to learn more. You’ve gotten so much better at explaining and making visual effects to help understand what’s going on with the physics.
Thanks for the video

[veritasium]

It was apparently 800V, so you can do the math on the resistance ;)

[Czesnek]

I really wanted to touch the levitating plate, but then they showed how hot the plate is.

[peronkop]

"Tell me this is not the best dinner center piece"

[ForestGirlTeresa]

I was a Hull Technician in the Canadian Navy, serving on a Destroyer. I switched on our welder, and the cable was mounted on the steel wall, coiled up. As I passed this cable, all the tools shot out of my belt and stuck to the wall inside the coil. I learned an interesting lesson about magnetic fields.

[LoiselsPhotography]

Everything is science. This is just called being knowledgeable.

[cbrooks]

Please make more videos like this. I absolutely love the history of science!

[OrgoMadeEasy]

Wow, that's some incredibly amazing stuff Derek. Thanks for making this video! Idk why I was so surprised by the light bulb part. 

[EvanArizona]

This is the coolest thing Iv'e ever seen.

[JimC]

Thank you for this video! In the Museum of Science and Industry in Chicago, in the late 50s and early 60s when I was a kid, they used to have a similar device that worked the same way. It was demonstrated in the Electric Theater. That one was relatively portable (with casters) and smaller: IIRC, the size of a large hassock.

The demonstrator would wheel it on stage and show the levitation of the aluminum plate. He (always "he" in those days) didn't have the light fixture, though. He never mentioned any of the electrical specs, but the machine gave off a distinct hum. He did show that if you pressed down on the plate, the humming would get louder. That showed the plate didn't get that hot in the short demo time, so spraying water on it wouldn't be dramatic (but he did mention the plate got warm). Also, the machine didn't have anything to prevent water from dripping into it.

The Electric Theater was so cool! It was my favorite place. First time I saw strobe lights, UV light, and a microwave transmitter as big as a refrigerator. The last had two small plates on bars on the front (transmitting antennas, I guess), and he had an ear of popping corn on a stick that he placed between them, and the corn would pop on the ear! You could smell the fresh popcorn! Totally magic at the time! Imagine how I felt when compact microwave ovens started showing up around 1970!

He also had a setup that would catch the shadow of an exploding balloon with a synchronized strobe flash on a phosphorescent screen! Now anyone can see high-speed videos of that, but at the time it was completely

[Srivatssan]

Best explained. College teaching Bachelors in Engineering should show this video to its students which will make them understand induction better. Nice work.

[black_platypus]

1:24 What's a _wah_ ?
...
...Oooh, he means "wire"!

[bernd_the_almighty]

Awesome invention, it levitates, gives you light, and you can cook on it.

[DBear]

Michael Faraday...One of the greatest minds that ever was yet hardly know outside of the scientific community! Definition of a paradox right there!

[vamshisaikrishnaarelli]

It is the best science channel I've ever come across... Love you to peaks.💖

[familiasgte]

Faraday - Attempting to create the Arc Reactor before it was cool.