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Assertion : The materials which have ver...

Assertion : The materials which have very small range of plastic extension are called brittle material.
Reason: If the stress is increased beyond the elastic limit, the material will break.

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To analyze the assertion and reason provided in the question, we will break down the concepts of brittle materials, elastic limit, and the behavior of materials under stress. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that materials with a very small range of plastic extension are called brittle materials. - **Explanation**: Brittle materials exhibit little to no plastic deformation before breaking. When stress is applied, they reach their elastic limit quickly and fail without significant plastic deformation. 2. **Understanding the Reason**: - The reason states that if the stress is increased beyond the elastic limit, the material will break. - **Explanation**: This statement is generally true for all materials. When stress exceeds the elastic limit, materials can either deform plastically or break, depending on their properties (ductile vs. brittle). 3. **Analyzing the Stress-Strain Graph**: - A stress-strain graph can help visualize the behavior of materials under stress. - **Key Points**: - The initial linear portion represents the elastic region where the material will return to its original shape when the stress is removed. - The point where the material transitions from elastic to plastic deformation is known as the elastic limit. - Brittle materials will show a very small plastic region and will break shortly after reaching the elastic limit. 4. **Conclusion**: - The assertion is correct because brittle materials do have a small range of plastic extension. - The reason is somewhat misleading because it does not specify which type of material it refers to; it applies to both brittle and ductile materials. Thus, while the statement is true, it is not entirely accurate in the context of the assertion. ### Final Answer: - **Assertion**: True - **Reason**: Partially true but lacks specificity. Therefore, the assertion is correct, but the reason is not adequately explained.
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