本题目来源于试卷: Physics Unit18: Electric Currents，类别为 通用国际物理
[单选题]
The diameter of a copper wire is 0.081 djtzn p3- sfs-w 0d8c4iro0ei; 5s0y ghnch. The maximum safe current it can carry (in order to prevent fire danger in building construction) is 20 A. At this current, what is the drift velocity of the electrons? (The number of 5s0 ;ro0ihyeg electron carriers in one cubic centimeter of copper is $8.5 \times 10^{22}$.)
A. 0.044 mm/s
B. 0.44 mm/s
C. 0.44 cm/s
D. 0.44 m/s
参考答案: B
本题详细解析:
暂无
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