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A 5 watt source emites monochromatic lig...

A 5 watt source emites monochromatic light of wavelenght `5000 overset@A`. When placed 0.5m away, it liberates photoelectrons from a photosensitive metallic surface. When the source is moved to a distance of 1.0m, the number of photo electrons liberates will:

A

be reduced by a factor of 2

B

be reduced by a factor of 4

C

be reduced by a factor of 8

D

be reduced by a factor of 16

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