Two wires of equal length and cross-section are suspended as shown. Their Young's moduli are Y1 and Y2, respectively. The equivalent Young's modulus will be:
Correct answer: B. (Y1 + Y2) / 2
- A. Y1 + Y2
- B. (Y1 + Y2) / 2
- C. (Y1 * Y2) / (Y1 + Y2)
- D. √(Y1 * Y2)
Explanation
The correct answer is Option B: (Y1 + Y2) / 2. Option A is incorrect because it implies a linear addition of moduli, which is applicable in parallel arrangements, not series. Option C is incorrect because it reflects a division of stress in a different context. Option D shows the geometric mean.
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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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