The Young's modulus of a wire of length L and radius r is Y N/m2. If the length and radius are reduced to L/2 and r/2, then its Young's modulus will be
Correct answer: B. Y
- A. Y/2
- B. Y
- C. 2Y
- D. 4Y
Explanation
The Young's modulus (Y) is an intrinsic property of a material that describes its stiffness, and it is independent of the dimensions, such as length and radius of the wire. Therefore, even if the length and radius of the wire are reduced to L/2 and r/2, respectively, the Young's modulus remains unchanged. It only depends on the material itself and not its size or shape. Option A is incorrect because reducing dimensions does not alter Young's modulus. Option C and Option D incorrectly suggest that Young's modulus increases with reduced dimensions, which is not the case. The correct answer is Option B, as Young's modulus remains Y.
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About Physics of Solids
Solids are compared through crystal structure, amorphous arrangement, elasticity, plastic deformation, stress, strain and Young’s modulus. Electrical behavior depends on available charge carriers and band structure, so conductors, insulators and semiconductors must be distinguished from mechanical properties such as strength, stiffness and brittleness.
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