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A photo cell is illuminated by a small b...

A photo cell is illuminated by a small bright source placed 1m away When the same source of light is placed 2m away, the electrons emitted by photo cathode

A

carry one quarter of their previous energy

B

carry one quarter of their previous momenta

C

are half as numerous

D

are one quarter as numerous

Text Solution

Verified by Experts

The correct Answer is:
d

`Iprop(1)/(d^(2))`
When source is placed 2m away then `I=I//4` The number of electrons emitted is derectly proportional to intensity .Hence number of emitted electrons is reduced to one fourth
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Knowledge Check

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