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Assertion (A) : When tiny circular obsta...

Assertion (A) : When tiny circular obstacle is placed in the path of light from some distance, a bright spot is seen at the center of the shadow of the obstacle.
Reason (R ) : Destructive interference occurs at the centre of the shadow.

A

(a) If both assertion and reason are true and reason is the correct explanation of assertion.

B

(b) If both assertion and reason are true but reason is not the correct explanation of assertion.

C

(c) If assertion is true but reason is false.

D

(d) If assertion and reason both are false.

Text Solution

Verified by Experts

The correct Answer is:
C
The waves diffracted from the edges of circular obstacle, placed in the path of light, interfere constructively at the centre of the shadow resulting in the formation of a bright spot.
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Knowledge Check

  • A: When a tiny circular obstacle is placed in the path of light from a distant source, a bright spot is seen at the centre of the shadow of the obstacle. R: Waves diffracted from the edge of the circular obstacle interfere constructively at the centre of the shadow producing a bright spot.

    A
    IF both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
    B
    If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark(2)
    C
    IF Assertion is true statement but Reason is false then mark(3)
    D
    If both Assertion and Reason are false statements, then mark (4)

  • Interference fringes were produced using light in a doulbe-slit experiment. When a mica sheet of uniform thickness and refractive index 1.6 (relative to air) is placed in the path of light from one of the slits, the central fringe moves through some distance. This distance is equal to the width of 30 interference bands if light of wavelength 4800 is used. The thickness (in mu m ) of mica is

    A
    90
    B
    12
    C
    14
    D
    24
    • A2Z-WAVE OPTICS-Section B - Assertion Reasoning
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    4. Statement-I : In Young's double slit experiment interference pattern d...

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    8. Statement I: In Young's double-slit experiment, the two slits are at d...

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    9. Assertion : No diffraction is produced in sound waves near a very smal...

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    13. Statement I: In Young's experiment, for two coherent sources, the resu...

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    14. Assertion: When a light wave travels from a rarer to a denser medium, ...

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    16. Assertion (A) : No interfrence pattern is detected when two coherent s...

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    17. Assertion (A) : The flim which appears bright in reflected system will...

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    19. Assertion (A) : In YDSE, the fringes become indistinct if one of the s...

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    20. Assertion (A) : The unpolarised light and polarized light can be disti...

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