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Assertion : Stress is the internal for...

Assertion : Stress is the internal force per unit area of a body.
Reason : Rubber is less elastic than steel.

A

Both assertion and reason are true and the reason is the correct explanation of the assertion

B

Both assertion and reason are true but the reason is not the correct explanation of the assertion

C

The assertion is true but the reason is false

D

The assertion and reason both 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: Analyze the Assertion The assertion states that "Stress is the internal force per unit area of a body." - **Definition of Stress**: Stress is defined as the internal force (F) acting on a material divided by the area (A) over which the force acts. Mathematically, it is expressed as: \[ \text{Stress} = \frac{F}{A} \] - **Conclusion**: The assertion is true because it accurately describes the definition of stress in physics. ### Step 2: Analyze the Reason The reason states that "Rubber is less elastic than steel." - **Definition of Elasticity**: Elasticity is the property of a material to return to its original shape and size after the deforming force is removed. It is quantitatively expressed as the ratio of stress to strain. - **Comparison of Rubber and Steel**: - Rubber is a more flexible material and can undergo larger deformations (greater strain) when subjected to the same amount of stress compared to steel. - Steel, on the other hand, has a higher elastic modulus, meaning it is stiffer and returns to its original shape more readily after deformation. - **Conclusion**: The reason is true because rubber indeed is less elastic than steel. ### Step 3: Determine the Relationship Between Assertion and Reason - While both the assertion and reason are true, the reason does not explain the assertion. The assertion is about the definition of stress, while the reason discusses the comparative elasticity of two materials. ### Final Conclusion Both the assertion and reason are true, but the reason is not the correct explanation for the assertion. Therefore, the correct answer is: **B. Both assertion and reason are true, but the reason is not the correct explanation of the assertion.** ---
To solve the given question, we need to analyze both the assertion and the reason provided. ### Step 1: Analyze the Assertion The assertion states that "Stress is the internal force per unit area of a body." - **Definition of Stress**: Stress is defined as the internal force (F) acting on a material divided by the area (A) over which the force acts. Mathematically, it is expressed as: \[ \text{Stress} = \frac{F}{A} ...
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