A circular tablet with a radius of 20 cm and a uniform luminosity of 10.5 cd / m ^ 2 illuminates a small flat surface with an area of 1 cm ^ 2 and at a distance of 1 m from the center of the tablet. The orientation of this small surface is such that its perpendicular to the line joining the centers of the two surfaces forms an angle of 45 °. This line is perpendicular to the circular disk. Determine the luminous flux on a small surface

A circular tablet with a radius of 20 cm and a uniform luminosity of 10.5 cd / m ^ 2 illuminates a small flat surface with an area of 1 cm ^ 2 and at a distance of 1 m from the center of the tablet. The orientation of this small surface is such that its perpendicular to the line joining the centers of the two surfaces forms an angle of 45 °. This line is perpendicular to the circular disk. Determine the luminous flux on a small surface

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