I tried to experiment the mysterious phenomenon that aluminum floating in the air melts

A movie saying that a massive aluminum block floats in the air, gradually melting in red and finally falling to the ground is a topic on YouTube and other video sites. Since the principle of roughly understand why aluminum masses melted and why they could float with fluff in the air, I decided to experiment with experiments.

HQ Melting Aluminuim w / Electro Magnetic Cylinder HQ - YouTube

On the front side of the camera is a coil that appears to be made of copper. Pick up the mass of aluminum over there with tweezers ... ...

Bring it to the center of the coil ......

In that position, I started floating in the air with fluffy. While shaking swaying, I keep the position around the center of the coil.

It seems that a strong current is flowing through the surrounding coils. Was it strengthening the current on the way, the movement of the aluminum chunk which had been swinging until then stopped and changed the angle to stand upright.

And gradually it gradually begins to melt in red. The shape which was cylindrical also melted and became soft like a crown, so corners were removed and it was stretched up and down.

When I switch off the current, it falls to the ground "Botatsu" in a moment and hardens ... ...

After a few seconds, I returned to the ticking aluminum plate.

◆ Wake melted aluminum mass
The aluminum masses melted even though they were not blazing with fire, "Induction heatingThis phenomenon is called a phenomenon called. The magnetic field generated by the high-frequency current flowing through the coil penetrates the mass of aluminum, so that aluminum not directly contacted is "Eddy currentCurrent is generated called. As this eddy current continues to flow, the aluminum itself generates heat and finally melts with high heat.


"Inductive Heating" is called "Induction Heating" in English, its initial letter "IH"This phenomenon is also used for" IH cooker "which cooks frying pan and kettle hotly.


◆ What is the force that floats the aluminum ingot in the air?
So, what is the reason why aluminum lumps floated in the air? Speaking of what is well known as floating in the air, floating the car body with strong magnetic force due to superconductivity, traveling at 500 kilometers per hourLinear motor carAlthough there are aluminum chunks that appeared in movies as floating in the air in the same mechanism as the linear motor car as a principle.

However, aluminum should normally be a material that is almost non-magnetic. It also gives the magnetic power to such aluminum, giving the power enough to float itself,Electromagnetic inductionEddy current generated byAlternating electromagnetic fieldWith this force, this phenomenonMagnetic levitationIt is called.

The phenomenon of magnetic levitation can be easily reproduced even at home if there is only IH cooker. First of all, we prepare a commercially available aluminum foil and a tubular one made of a material that does not pass electricity such as paper. The core of the kitchen paper is reflected in the picture. In addition, depending on the situation at the time of the experiment, there is a possibility that a spark may come out from aluminum foil. Please pay attention to the experiment carefully, please prepare to put water in a cup etc. so that you can extinguish immediately even if a fire comes out.

Cut the aluminum foil to a size of 20 centimeters square and fold it in the manner of origami.

In addition to folding.

Then cut out the corners where the four overlap with scissors, and drill a hole in the center of the aluminum foil.

If you extend the aluminum cut out into a sector .........

A hole opened in the aluminum foil.

Next, set the paper cylinder in the middle of the IH cooker and let the aluminum foil pass from the top.

And when turning on the power of the IH cooker, the aluminum foil, which should not touch anything, began up and down repeatedly up and down.

Aluminum foil floating up with an alternating electromagnetic field - YouTube

The force with which the aluminum foil floats is the energy of the magnetic field generated by the IH cooker. In the aluminum foil that received the magnetic fieldElectromagnetic inductionByInduced currentTo flowAlternating electromagnetic fieldOccurred. Thanks to that, because of the magnetic repulsion between the IH cooker and the aluminum foil, it means that the aluminum foil has floated up.

The main reason that aluminum foil repeats levitation every few seconds seems to be because the floating prevention sensor built in the IH cooker operated because the floating and distance has left. What is placed in front is a small tissue paper. It should fly together if it is floating with the force of the wind, but you can see the tissue is not making it fine.

In other words, the phenomenon that melted aluminum masses floating in the first movie is caused by the high frequency alternating current flowing through the coilmagnetic fieldAnd the magnetic field which jumped into the aluminum ingot was generated insideElectromagnetic inductionbyEddy current, And the eddy current itself isCurrent changeA magnetic field is generated by theseMagnetic forceBy repelling each other byMagnetic levitationThat's why it is happening. And the eddy current generated inside is heated by the electrical resistance of the aluminum bodyInduction heatingIt caused the aluminum mass to melt by the heat generated by himself.

It is energy of electricity and electromagnetic force invisible to the eyes, but you can see well that it is actually useful in many places.

in Science,   Video, Posted by darkhorse_log