| the tendency of an electric conductor or stream of charged particles to constrict, caused by the action of a magnetic field that is produced by a flow of electricity. |
| pinch effect n. Radial constriction of flowing plasma or other matter carrying an electric current, caused by the magnetic field that is produced by the current. |
pinch effect
self-constriction of a cylinder of an electrically conducting plasma. When an electric current is passed through a gaseous plasma, a magnetic field is set up that tends to force the current-carrying particles together. This force can compress the plasma so that it is heated as well as confined, but such a self-pinched plasma cylinder is unstable and will quickly develop kinks or break up into a series of lumps resembling a string of sausages. The pinch effect, therefore, must be augmented with other magnetic-field configurations to produce a stable magnetic bottle.
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