Selectively magnetized (hemi)sphere Answered
I'm looking for a way to construct a hemisphere,
- maybe 1.5" to 2" in diameter
- ideally with no moving parts
- where any of a number of areas on the surface could be magnetized at will
I thought of having an array of tiny electromagnets starting from middle and radiating to under the surface, but frankly, that would take a long time, and I figure there would be insulation issues.