The other arm carries a wire coil attached to an electric circuit in other words, an electromagnet.

ECONOMIST: Weighing a kilogram

And for those particles that make it past the caesium iodide, a huge electromagnet tracks their passage out of the detector.

ECONOMIST: How to build a B-factory

That is because a permanent magnet's maximum strength is dictated by the material it is made from, while an electromagnet's strength depends on the current passing through it.

ECONOMIST: Maglev trains

One was a kitchen chemistry set for growing crystals and the other a simple electronics kit, based partially around parts of a Snap Circuits set, that has kids building an electromagnet and lighting up an LED.

ENGADGET

Each segment has an electromagnet attached to it, and these are activated by a current that flows from head to tail in more or less the way that a nerve signal flows in a real animal.

ECONOMIST: Robots

In a paper in the Journal of Immunological Methods, Wendy Dittmer of Philips claims to have achieved a 100, 000-fold increase in detection speed by hurrying magnetically tagged molecules of parathyroid hormone towards the spin valve with an electromagnet instead of allowing them to diffuse there.

ECONOMIST: Labs on a chip