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Fun with an MRI Machine

submitted by winkler1

1 decade 5 years 11 months ago

gravity
, magnetism

This is a video of a couple of guys tipping over a block of aluminum inside of an MRI machine. Because of the huge magnetic field the Lenz force opposing gravity is enough that the block falls very, very slowly.

6 Comments

I bet they got an approval from their supervisor before sticking metal objects in the MRI machine...

^Well, not all metals are magnetic. Aluminium, which was used in this experiment, is paramagnetic. Paramagnetic materials typically couple quite weakly to magnetic fields, so I don't think there was any chance of the block causing harm, as opposed to this ferromagnetic object.

The reason it falls slowly is that it moves through a magnetic field, which induces a current in the metal. This current sets up its own magnetic field with opposite polarity to the external field.

ant

Move it closer in.

OK there it is... this must be a popular trick since the MRI tech I met showed it to me

*short

This video has been flagged as being less than 1 minute in length - declared short by maatc.

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