Задача 10686.

The radioactive nucleus, which flew out of the accelerator at a speed of 0.8 s, ejected a beta particle in the direction of its motion at a speed of 0.7 s relative to the accelerator. Find the speed of the particle relative to the nucleus.

A detailed solution with a brief note of the condition, formulas and laws used in the solution, the derivation of the calculation formula and the answer.
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