Magnetic confinement consists of containing material in the state of plasma inside a magnetic bottle, which is a magnetic field to which we have given a determined form so that the positive or negative particles that make up our plasma remain inside that bottle . This is achieved by the Lorentz force, which tells us that a charged particle that moves within a magnetic field experiences a force perpendicular to the vector of the magnetic field and to the displacement vector, whereby we obtain that the particle does not leave the field. The state of plasma is a state of aggregation of matter in which the thermal agitation is able to overcome the electric attraction that the electrons suffer by the atomic nuclei.
Magnetic confinement is useful because it allows us to heat material at temperatures where no material container would remain in solid state.
This phenomenon is also found in nature in the so-called Van Allen belts that protect us from the solar wind.
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