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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

I

C

2I

D

4I

Text Solution

Verified by Experts

The correct Answer is:
B
In both the cases, the intensity is same.
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CENGAGE PHYSICS-PHOTOELECTRIC EFFECT-Single Correct
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