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Can anyone help me with a radiometry problem

Can anyone help me with a radiometry problem

Can anyone help me with a radiometry problem

(OP)
Hi,

can anyone help me solve this problem

A classic problem of radiometry : how deep does a hole have to be such that if you're at the bottom of it, you are in total darkness. You may assume the minimum light your eye can detect is 0.003 cd per sq meter. You may also assume the illuminance of the sun isabout 120,000 lux at surface of earth. The angular size of the sun is about 0.5 degrees and it is about 1.5 x 10^8 km from earth?

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