Which characteristic of wires does a lower AWG number signify?

A lower AWG (American Wire Gauge) number indicates a thicker wire. The AWG system is a standardized wire gauge system used primarily in North America. In this system, as the gauge number decreases, the diameter and cross-sectional area of the wire increase. Therefore, a wire with a lower gauge number, such as 10 AWG, would be significantly thicker than a wire with a higher number, such as 20 AWG.

This characteristic is crucial in applications where wire thickness affects the current-carrying capacity, resistance, and overall performance of electrical systems. Thicker wires can carry more current and have lower resistance, making them suitable for high-power applications. The other options, such as insulation thickness, flexibility, or wire length, do not correlate with the AWG measurement and hence are not relevant to this characteristic of wire.