Задача 20649.

The concentration of radioactive atoms in the atmosphere increases linearly with height according to the law n = a * h, where a = 1 * 10 ^ 4m ^ -4, h - height. Rate of flow of the density of atoms in the earth, if the molar mass of the isotope is 14 g / mol, the mean free path length = 80 nm, the atmospheric temperature T = 300 K.

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