What factors impact the resistivity characteristics of metals ?
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Answer: E. All of the above
Explanation
Temperature changes alter thermal lattice vibrations, which directly increases electron scattering and electrical resistivity in metals. Alloying introduces foreign atoms into the crystal lattice, permanently disrupting electron flow and raising baseline resistivity levels. Cold work and age hardening introduce crystal defects and dislocations that impede electron movement and increase material resistivity. Resistivity in metallic conductors is governed by how frequently conduction electrons collide with lattice imperfections and phonons. Mechanical deformation like cold working increases dislocation density, which scatters charge carriers more frequently during conduction. Age hardening precipitates secondary phase particles that further hinder electron mobility through the microscopic metallic matrix.
Single factors like temperature alone are incomplete because alloying and mechanical hardening also significantly impact metal resistivity. Listing only cold work or age hardening ignores thermal effects and chemical alloying which heavily alter electron scattering. None of the options can be excluded since every listed mechanical and thermal factor genuinely impacts metal resistivity characteristics.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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