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A lens having focal length f and apertur...

A lens having focal length f and aperture of diameter d forms an image of intenjsity I. Aperture of diameter `(d)/2`in central region of lens in covered by a black paper. Focal length of lens and intensity of image now will be respectively

A

f and `1//4`

B

`3//4` and `1//2`

C

f and `31//4`

D

`f//2` and `1//2`

Text Solution

Verified by Experts

The correct Answer is:
C
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VMC MODULES ENGLISH-RAY OPTICS AND WAVE OPTICS -ENABLE
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