For the fusion of nuclei, it is necessary that positive nuclei overcome the forces of Coulomb repulsion and approach each other at a distance of the order of the size of the nuclei. for this they must have high kinetic energy, which is possible at a very high temperature – about 10 ^ 8 K
Temperature is a measure of the kinetic energy of particle motion. Such temperatures can be obtained, for example, by pre-using a nuclear reactor or using laser beams.
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