本题目来源于试卷: Physics Unit20: Magnetism，类别为 通用国际物理
[单选题]
A thin copper rod 1.0 m long has a mass of 0wxo1z71qhphk2w8;k9.xrb r k.050 k:kigkk7qsw,m 7zs(;ag and is in a magnetic field of 0.10 T. What minimum current in the rod is needed in order for the magnetic force to cancel the weight of the ;gz77:,askw(qisk mk rod?
A. $1.2 \; A$
B. $2.5 \; A$
C. $4.9 \; A$
D. $9.8 \; A$
参考答案: C
本题详细解析:
暂无
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