Задача 40961.

The minimum illumination rate for animals is E = 20 lx (incandescent lamps). Determine the luminous intensity of the lamp suspended at a height of h = 3 m. Calculate to make, provided that this illumination is created by two lamps located at a distance of l = 8 m from each other.

Detailed solution with a brief record of the conditions, formulas and laws used in the decision, the conclusion of the calculation formula and the answer.
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