Light of wavelength lambda from a point source falls on a small circular obstacle of diameter .d.. Dark and bright circular rings around a central bright spot are formed on a screen beyond this obstacle. The distace between the screen and obstacle is D. Then, the condition for the formation of rings is

Light of wavelength lambda from a point source falls on a small circul

1.	Light of wavelength lambda from a point source falls on a small circular obstacle of diameter .d.. Dark and bright circular rings around a central bright spot are formed on a screen beyond this obstacle. The distace between the screen and obstacle is D. Then, the condition for the formation of rings is
Answer» `LAMBDA APPROX (D)/(4)` `sqrt(lambda) approx (d)/(4D)` `lambda approx (d^2)/(D)` `d approx (lambda^2)/(D)` Answer :C

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