直流电动机不允许直接启动,启动时必须在电枢电路串联启动电阻或变阻器,且电阻值为最大,以后逐渐减小为零。
查看答案
直流电动机的调磁调速是恒功率调速。
A. 对
B. 错
The publication of the poet's most recent works will certainly _______ his nationalreputation.
A. magnify
B. strengthen
C. enlarge
D. enhance
The workers’ demands are ____: they are asking for only a small increase in their wages.
A. normal
B. moderate
C. inadequate
D. insignificant
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