These coils are normally used to select slices for creating three-dimensional images, but the magnetic fields they create can also be used to exert a force on a small magnetic object inside a scanner.

这些线圈通常用于选择建立三维图像的切片，但是它们所建立的磁场也能被用来在扫描仪内部的小磁性物体上施加作用。

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A compass is a device containing a metal object that points toward the magnetic north pole.

VOA: special.2010.07.14

Maglev technology has been around for years as the propulsion method behind certain European and Asian trains, and basically involves using the Physics 101 properties of magnetic attraction and repulsion to provide an object with momentum.

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The magnetometer will record what, if any, magnetic field the asteroid has, thus revealing whether it was ever part of an object large enough to have possessed the molten iron core needed to generate such a field.

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They intend to do more in-depth observations of the object in the near future, searching for details about its pulsation and its magnetic field.

MSN: Runaway star may be fastest pulsar yet - Technology & science - Space - Space.com | NBC News