What is the ratio of illuminance at a point 5m just below ___

What is the ratio of illuminance at a point 5m just below a lamp emitting 100 candelas and at a point 5m away from the first point on the same horizontal plane?

A. 1:2
B. 2√2 : 1
C. 1: 2√2
D. 2:1

Show Answer

Answer: B

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