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Optics JEE mains PYQ

 Q. A convex lens of focal length 40 cm forms an image of an extended source of light on a photo- electric cell. A current 1 is produced. The lens is replaced by another convex lens having the same diameter but focal length 20 cm. The photoelectric current now is:

                                                        (JEE mains 2024)

1. I/2


2. 4I


3. 2I


4. I

And: I

As amount of energy incident on cell is same so current will remain same.

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