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In a YDSE with two identical slits, when...

In a YDSE with two identical slits, when the upper slit is covered with a thin, perfectly tranparent sheet of mica, the intensity at the centre of screen reduces ro `75%` of the initial value. The second minima is observed to above this point and third maxima below it. which of the following can not be a possible value of phase difference caused by the mica sheet

A

`(pi)/(3)`

B

`(13pi)/(3)`

C

`(17pi)/(3)`

D

`(11pi)/(3)`

Text Solution

Verified by Experts

The correct Answer is:
A
`I'=(3)/(4)(4I)=3I`
So `4I=I+I+2Icosphiimpliescosphi=(1)/(2)impliesphi=(pi)/(3)`
But value should lie between `3pi` & `6pi`
So it cannot be `(pi)/(3)`
for second minima `phi=3pi`
for third maxima `phi=6pi`
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ALLEN-WAVE OPTICS-Exercise 1 (Check your Grasp)
  1. Minimum thickness of a mica sheet having mu=(3)/(2) which should be pl...

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

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

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

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  5. Diffraction and interference of light refers to -

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

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

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

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  9. Diffraction initiated from obstacle, depends upon the

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  10. Phenomenon of diffraction occurs

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

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  12. which of the following any gives more distinct diffraction

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  13. All fringes of diffraction are of-

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

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

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

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  17. Red light is generally used to observe diffraction pattern from single...

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  18. Calculate angular width of central maxima if lamda=6000Å,a=18xx10^(-5)...

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  19. In single slit fraunhoffer diffraction which type of wavefront is requ...

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  20. In the diffractin pattern of a single slit aperture, the width of the ...

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