Задача 50170.

The red laser beam operating at a wavelength lambda = 630 nm. It has the form of a cone with an angle of divergence of 10 ^ -4 rad. The radiated laser power Po = ZmVt. At what maximum distance L observer can see the laser light when the eye reliably detects 100 photons per second. Pupil diameter d = 0,5 cm. The absorption of light is not taken into account. The beam diameter at the laser output is much less than d.

Detailed solution shorthand terms, formulas, laws used in the decision, the withdrawal of the calculation formula and the response.

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