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Assertion : If we look clearly at the sh...

Assertion : If we look clearly at the shadow cast by an opaque object, close to the region of geometrical shadow, alternate dark and bright regions can be seen.
Reason : This happens due to the phenomenon of interference.

A

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

B

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

C

If assertion is true but reason is false.

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given question, we need to analyze both the assertion and the reason provided. ### Step 1: Understand the Assertion The assertion states that when observing the shadow cast by an opaque object, particularly near the edges of the shadow, we can see alternate dark and bright regions. This phenomenon occurs due to the diffraction of light. ### Step 2: Define Diffraction Diffraction is the bending of light waves around the edges of an obstacle or aperture. When light encounters an opaque object, it does not just create a sharp shadow; instead, the light waves bend around the edges, leading to a pattern of alternating light and dark regions. ### Step 3: Confirm the Assertion Since diffraction causes the formation of these alternating dark and bright regions near the shadow, we conclude that the assertion is true. ### Step 4: Understand the Reason The reason provided claims that the alternating dark and bright regions occur due to the phenomenon of interference. ### Step 5: Define Interference Interference is the phenomenon that occurs when two or more coherent light waves overlap and combine, resulting in a pattern of alternating bright and dark fringes. In interference, the bright and dark fringes typically have the same intensity. ### Step 6: Analyze the Reason The reason given in the question is incorrect because the observed pattern near the shadow is not due to interference but rather due to diffraction. Therefore, while the assertion is true, the reason is false. ### Conclusion Based on the analysis: - **Assertion**: True (due to diffraction) - **Reason**: False (it is not due to interference) Thus, the correct answer is that the assertion is true, but the reason is false. ---
To solve the given question, we need to analyze both the assertion and the reason provided. ### Step 1: Understand the Assertion The assertion states that when observing the shadow cast by an opaque object, particularly near the edges of the shadow, we can see alternate dark and bright regions. This phenomenon occurs due to the diffraction of light. ### Step 2: Define Diffraction Diffraction is the bending of light waves around the edges of an obstacle or aperture. When light encounters an opaque object, it does not just create a sharp shadow; instead, the light waves bend around the edges, leading to a pattern of alternating light and dark regions. ...
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