Copper is generally considered the most ideal conductor for electrical wiring. Which material is it?

• A. Aluminum
• B. Iron
• C. Copper
• D. Plastic

Answer: (C)

High electrical conductivity is the main criterion for a practical wiring conductor. Copper provides the best combination of high conductivity (low resistivity), workability, and durability. Because electrons move easily through copper, a wire can carry more current with less resistance and heating for a given size. Copper is also very ductile, so it can be drawn into long, thin wires and bent around corners without breaking, and it forms reliable joints with soldering or crimping. It resists corrosion in typical environments, supporting long-term reliability. Aluminum is lighter and cheaper but conducts less well and needs larger cross-sections plus special handling to manage oxide formation and connections. Iron has higher resistivity, leading to more heat for the same current. Plastic is an insulator, not a conductor. For these reasons, copper remains the standard material for electrical wiring.