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A caesium photocell, with a steady poten...

A caesium photocell, with a steady potential difference of 60 V across it, is illuminated by a bright point source of light 50 cm away. When the same light is placed 1 m away the photoelectrons emitted from the cell

A

are one quarter as numerous

B

are half as numerous

C

each carry one quarter of their previous momentum

D

each carry one quarter of their previous energy.

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