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Two point source separated by d=5mum emi...


Two point source separated by `d=5mum` emit light of wavelength `lamda=2mum` in phase A cicular wire of radius `20mum` is placed around the source as shown in figure.

A

Points A and B are dark and points C and D are bright.

B

Point A and B are bright and point C and D are dark

C

Point A and C are dark and points B and D are bright.

D

Points A and C are bright and points B and D are dark.

Text Solution

Verified by Experts

The correct Answer is:
D
Path difference for points A & C is O so constructive interference take place.
Path difference for B & D `=5mum=(5lamda)/(2)`
So distructive interference take place.
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ALLEN -WAVE OPTICS-Exercise 1 (Check your Grasp)
  1. Let S(1) and S(2) be the two slits in Young's double-slit experiment. ...

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  2. When light is refracted into a medium

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  3. Two point source separated by d=5mum emit light of wavelength lamda=2m...

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  4. Two coherent narrow slits emitting light of wavelength lamda in the sa...

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  5. Minimum thickness of a mica sheet having mu=(3)/(2) which should be pl...

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  6. In the YDSE shown the two slits are covered with thin sheets having th...

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  7. In a YDSE with two identical slits, when the upper slit is covered wit...

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  8. Light wavelength 650 nm is incident normally upon a glass plate the gl...

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  9. Diffraction and interference of light refers to -

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  10. The phenomenon of diffraction of light was discovered by-

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  11. Sound waves shown more diffraction as compare to light rays-

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  12. The conversation going on, in some room, can be heared by the person o...

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  13. Diffraction initiated from obstacle, depends upon the

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  14. Phenomenon of diffraction occurs

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  15. Diffraction of light is observed only, when the obstacle size is-

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  16. which of the following any gives more distinct diffraction

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  17. All fringes of diffraction are of-

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  18. A single slit of width d is placed in the path of beam of wavelength l...

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  19. Direction of the first secondary maximum in the Fraunhofer diffraction...

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  20. Angular width (beta) of central maximum of a diffraction pattern on a ...

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