The steel reinforcement of ACSR allows longer spans, less sag, and shorter structures.

• A. Better grounding
• B. Longer spans
• C. Less corrosion
• D. Shorter spans

Answer: (B)

The key idea is that adding a steel core to the conductor increases its tensile strength, which lets the line be stretched farther between supports. In ACSR, the steel core carries most of the mechanical load from the conductor’s weight and wind, while the aluminum outer strands provide conductivity. Because the steel core can withstand higher tension, transmission lines can span longer distances without exceeding allowable sag, and the towers can be spaced farther apart. This is why longer spans is the best answer. The other points aren’t the primary effect of the steel reinforcement: grounding quality isn’t directly about the conductor’s strength, corrosion resistance isn’t the main outcome of reinforcing with steel in this context, and shorter spans would require more towers, not fewer.