Задача 40143.

The minimum illumination standard for keeping birds is 60 lux. Determine the luminous intensity of the lamp that must be hung at a height of 2 m in order to create such illumination under it.

Detailed solution with a brief record of the conditions, formulas and laws used in the solution, derivation of the calculation formula and answer.
If you have any questions regarding the solution, please write. I try to help.