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Assertion: From the relation Y = (Fl)/(...

Assertion: From the relation Y `= (Fl)/(ADeltal)`, we can say that, if length of a wire is doubled, its young's modulus of elasticity will also becomes two times.
Reason : Modulus of elasticity is a material property.

A

(a) If both Assertion and Reason are true and the Reason is correctn explanation of the Assertion.

B

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

C

If Assertion is true, but the Reason is false.

D

If Assertion is false but the Reason is true.

Text Solution

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The correct Answer is:
To solve the question, we need to analyze both the assertion and the reason provided. ### Step 1: Understand the Assertion The assertion states that from the relation \( Y = \frac{Fl}{A \Delta l} \), if the length of a wire is doubled, its Young's modulus of elasticity will also become two times. **Analysis**: - Young's modulus \( Y \) is defined as the ratio of stress to strain. - Stress is defined as \( \frac{F}{A} \) (force per unit area), and strain is defined as \( \frac{\Delta l}{l} \) (change in length per original length). - From the formula \( Y = \frac{Fl}{A \Delta l} \), if we double the length \( l \), we must also consider how the change in length \( \Delta l \) behaves. ### Step 2: Understand the Reason The reason states that modulus of elasticity is a material property. **Analysis**: - Young's modulus is indeed a material property, meaning it is intrinsic to the material itself and does not depend on the dimensions of the material (like length or area). - Therefore, regardless of the length of the wire, the Young's modulus for a specific material remains constant. ### Step 3: Conclusion Since the assertion incorrectly states that doubling the length of the wire will double its Young's modulus, while the reason correctly identifies that Young's modulus is a material property, we can conclude: - **Assertion**: False - **Reason**: True ### Final Answer The correct option is that the assertion is false and the reason is true. ---

To solve the question, we need to analyze both the assertion and the reason provided. ### Step 1: Understand the Assertion The assertion states that from the relation \( Y = \frac{Fl}{A \Delta l} \), if the length of a wire is doubled, its Young's modulus of elasticity will also become two times. **Analysis**: - Young's modulus \( Y \) is defined as the ratio of stress to strain. - Stress is defined as \( \frac{F}{A} \) (force per unit area), and strain is defined as \( \frac{\Delta l}{l} \) (change in length per original length). ...
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