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Assertion:- Materials can be stretched e...

Assertion:- Materials can be stretched even beyond proportionality limit. (point till which Hooke's law is valid is called proportionality limit)
Reason:- Elastic forces can be conservative even beyond proportional limit.

A

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

B

Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

C

Assertion is correct but Reason is wrong

D

Both Assertion and Reason are wrong

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given assertion-reason question, we will analyze both the assertion and the reason separately. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that materials can be stretched even beyond the proportionality limit. The proportionality limit is the point up to which Hooke's law is valid, meaning that stress is directly proportional to strain. - **Conclusion**: This assertion is true. Materials can indeed be stretched beyond the proportionality limit, although they may not obey Hooke's law in that region. 2. **Understanding the Reason**: - The reason states that elastic forces can be conservative even beyond the proportionality limit. A conservative force is one where the work done in moving an object between two points is independent of the path taken. - **Analysis**: When a material is stretched beyond the proportionality limit, it may exhibit plastic deformation, where the material does not return to its original shape. In such cases, the work done is not recoverable, indicating that the elastic forces are not conservative. - **Conclusion**: This reason is false. Elastic forces do not remain conservative beyond the proportionality limit. 3. **Final Evaluation**: - Since the assertion is true and the reason is false, the correct option for this assertion-reason question is that the assertion is correct but the reason is incorrect. ### Final Answer: The assertion is true, but the reason is false.
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