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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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When a tiny circular obstacle is placed in the path of light from a distance source, a bright spot is seen at the centre of the shadow of the obstacle. Explain. Why?

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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.

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    B
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