新投运电容器组应进行()合闸冲击试验。 ["A.3次","B.5次","C.7次","D.1次"]
N型半导体中的少数载子是()。 ["电子","离子","电洞","质子"]
在本质半导体加入三价的硼,则成为()。 ["N型","P型","NPN型","PNP型"]
RLC并联电路于谐振时其输入端电流大小为何?() ["电流为最小","电流为最大","电流为直流","等于零"]
当12伏特的电池提供0.15安培的电流于一个负载上时,此负载之输入电阻为何?() ["8欧姆","80欧姆","100欧姆","800欧姆"]
精液品质检查的意义有哪些?