World's Strongest Magnetic Field Is Demonstrated

lazarus_ writes "PORTLAND, Ore. -- Researchers at Florida State University's National High Magnetic Field Laboratory in Tallahassee achieved the holy grail of magnetism recently when their high-temperature superconductor attained the coveted 25-Tesla field strength record."

Comments

Southern Metalhead Population Devastated

[robdeadtech]

Metalheads from as far south as Miami, as far north as Atlanta, and as far west as Memphis were seen hurtling through the air at breakneck speed headed toward the city of Tallahassee.

Tampa, known for it's unusually dense Death Metal population, was particularly hard hit.

Don't connect ohmmeters to superconducting magnets

[G4from128k]

I worked at a place about 17 years ago that was using a superconducting magnet (3-5 T) and the "owners manual" expressly forbade attaching an ohmmeter to the magnet coil to see if the coil had become cold enough to superconduct. The problem was that at even low milliampere currents, the coil could store about as much energy as a photographic flash capacitor. Disconnecting the ohmmeter could create a nasty zap and possibly create a damaging arc inside the coil.

The field was quite fun if you didn't care about your credit cards. You could feel the eddy current drag on a penny if you moved it in the field and copper rings would fall in slow motion.

Ah! The good old days!

Re:Ok

[PurpleFloyd]

No, this is the largest magnetic field ever created (that we know about), although it does cover a fairly small area. The Earth's magnetic field is weak but very, very large; magnetic fields drop off rapidly (Inverse cube of distance, if I recall correctly) as you move away from the source. Similarly, speaker magnets are fairly weak (on the order of a few hundred to a thousand gauss) but since they are large, they affect a greater area than a small rare-earth magnet that has a 1 Tesla (10,000 Gauss) field strength - a few meters away, the magnetic field is lost in the "background noise" of the Earth's magnetic field. While this is almost certainly smaller than a tiny rare-earth magnet, it still won't cause compass needles all over the Earth to point in funny directions; just those around the building it's installed in. In summary: powerful magnet != big field.