【判断题】继电器用来控制大电流电路而接触器用来控制小电流电路。
【简答题】Henry found work in a bookstore after he finished middle school. He wouldn’t do anything but wanted to get rich. Mr. King thought he was too lazy and was going to send him away. Henry was afraid and h...
【判断题】继电器用来控制大电流电路,而接触器则用来控制小电流电路,继电器触点容量不大于5A。
【简答题】系统任务和系统函数依据实现的功能不同可以分为几类
【单选题】下面对《雁门太守行》的赏析不正确的一项是( )
A.
这首诗以色彩斑斓的词语描绘了悲壮的战争风云。
B.
“黑云压城城欲摧”渲染了敌军兵临城下的紧张气氛和危急形势。
C.
“霜重鼓寒声不起”一句写将士们黑夜行军和投入战斗。“声不起”形容鼓声低沉。
D.
“报君黄金台上意”一句,引用了战国时齐威王在易水东南筑台,置千金招揽人才的典故。
【单选题】下列人类细胞中染色体数目是23条的是()。
【简答题】Henry found work in a bookstore after he finished middle school. He wouldn’t do anything but wanted to get rich. Mr King thought he was too lazy and was going to send him away. Henry was afraid and ha...
【判断题】继电器用于切换小电流的控制电路,而接触器则用来控制大电流电路。
【单选题】下列选项属于常用的网络营销方法的是( )。
【单选题】()由触点辅入控制,可以把变频器的故障和电机过热保护继电器的输出用来控制交流接触器,使整个系统从输入侧切断电源,从而对系统起到彻底的保护作用,避免故障扩大。