单选题The purpose of DC generator brushes is to （）.Aneutralize armature reactionBconduct electric current to an outside circuitCconvert DC current to AC currentDprovide excitation to a DC generator
单选题
The purpose of DC generator brushes is to （）.
A
neutralize armature reaction
B
conduct electric current to an outside circuit
C
convert DC current to AC current
D
provide excitation to a DC generator
参考解析
解析：
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相关考题：
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