When a point source of light is at a distance of one metre from a phot – McqOptions

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1.	When a point source of light is at a distance of one metre from a photo cell, the cut off voltage is found to be V. If the same source is placed at 2 m distance from photo cell, the cut off voltage will be
A.	V
B.	V/2
C.	V/4
D.	\[V/\sqrt{2}\]
Answer» B. V/2

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