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A lens of focal length f gives diffracti...

A lens of focal length f gives diffraction pattern of Fraunhoffer type of a slit having width a. If wavelength of light is `lambda`, the distance of first dark band and next bright band from axis is given by

A

`a/lamda"" f`

B

`lamda/a ""f`

C

`lamda/(af)`

D

`a lamda f`

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The correct Answer is:
B
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TARGET PUBLICATION-WAVE THEORY OF LIGHT -EVALUATION TEST
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