We increase the length of the wire, thus increasing its resistance. 我们增加导线的长度，从而增加了导线的电阻。
The resistance of any length of a conducting wire is easily measured by finding the potential difference in volts between its ends when a known current is flowing. 已知导线中的电流，只要求出导线两端电位差的伏特数，就不难测出何任长度的导线的电阻。
