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An image of the sun is formed by a lens,...

An image of the sun is formed by a lens, of the focal length of 30 cm, on the metal surface of a photoelectric cell and a photoelectric current I is produced. The lens forming the image is then replaced by another of the same diameter but of focal length 15 cm. The photoelectric current in this case is

A

`I//2`

B

`2I`

C

`I`

D

`4 I`

Text Solution

Verified by Experts

The correct Answer is:
C
The current `I` is proportional to light energy falling on the lens per second with is same in the two cases. Hence same `I`.
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