皮皮学,免费搜题
登录
搜题
【单选题】
在三相异步电动机的顺序启、停控制中,可以利用哪种低压电器实现电动机顺序启、停的自动控制( ) 。
A.
时间继电器
B.
速度继电器
C.
过电压继电器
D.
欠电流继电器
拍照语音搜题,微信中搜索"皮皮学"使用
参考答案:
参考解析:
知识点:
.
..
皮皮学刷刷变学霸
举一反三
【单选题】---Could you tell me _________ tomorrow morning? ---Well, it will start at half past eight.
A.
when the meeting will start
B.
when the meeting started
C.
when will the meeting start
【单选题】He (start) swimming at the age of eight.
A.
start
B.
started
C.
is starting
D.
have start
【简答题】力偶对其作用平面内任一点之矩都等于力偶矩,而与________无关。
【简答题】力偶对任一轴上的投影代数和(),力偶对其作用平面内任一点之矩恒等于()。
【简答题】力偶对其作用平面内任一点之矩都等于力偶矩,而与 无关;力偶在任一轴上的投影等于 。力偶只能与 平衡。
【简答题】按要求完成句子。 1.  We start school at eight o'clock.  (改为否定句) We _____ _____ school at eight o'clock. 2. They have lunch at school. (改为一般疑问句, 并作肯定回答) _____ they _____ lunch at school? _____,  they _____. 3....
【简答题】力偶对其作用平面内任一点之矩都等于力偶矩,而与矩心位置 关。
【单选题】Let's start the trip ______ half past eight ______ the morning of February 21. [     ]
A.
at; on
B.
at; in
C.
/; in
D.
about; by
【单选题】Let’s watch the news on CNN. It at eight o’clock.
A.
will start
B.
is starting
C.
is going to start
D.
starts
【简答题】听下面的对话,回答1-2题。 1. When does Peter's school day start? [     ] A. At eight B. At eight fif C. At eight twenty-five 2. Who finds English very interesting? [     ] A. Millie. B. Peter. C. Lucy.
相关题目: