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A photocell is illuminated by a small br...

A photocell is illuminated by a small bright source placed 1 m away. When same source of light is placed 1/2 m away, the no. of photoelectrons emitted would :

A

decrease by a factor of 2

B

increase by a factor of 2

C

decrease by a factor of 4

D

increase by a factor of 4.

Text Solution

Verified by Experts

The correct Answer is:
D
`Iprop (1)/(r^(1)), "when" r.=(r)/(2)`
`I.=4I`
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