Задача 50316.

At a certain maximum value retention potential difference of the photocurrent with lithium surface illuminated by light with a wavelength of lyambda0 stops. By changing the wavelength of the radiation factor of 1.5, we determined that it is necessary to increase the retarding potential difference of 2 times to stop the photocurrent. Calculate lyambda0. electron work function of 2.39 eV.

Detailed entry, formulas and laws used in the decision, the withdrawal of the formula.
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