A split magnet is a magnet built in two halves with a small gap separating the halves to allow access to the strong magnetic field between them.
As of July 2011, the strongest split magnet in the world is located at the National High Magnetic Field Laboratory at Florida State University, with a field of 25 tesla. This electromagnet uses a current of 160,000A and requires 3,500 gallons of cooling water per minute.
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Split magnet Wikipedia(Text) CC BY-SA