电机为什么不能连续多次开停？_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题问答题简答题

电机为什么不能连续多次开停？

答案

参考答案：

电动机启动时有很大的启动电流，这个电流高达正常运行电流的5-7倍，因而电机线圈会产生较大热量，如果多次连续启动，尤其是带负荷启动时，启动电流极大.启动后，产生的热量尚未散发即停下又启动，必须使线圈温度升高，严重时，烧坏电机，故一般不允许连续多次启动。

单项选择题

平面滑动时，滑动面的倾角β与坡面倾角α的关系是（）

A.β=α

B.β>α

C.β<α

D.β≥α

选择题

Waiting for the airplane to take off, I was happy to get a seat by myself. Just then, a flight attendant 41 me and asked, "Would you mind changing your seat? A couple would like to sit together. “The only other 42 seat was next to a woman with both arms in casts（石膏）, a black-and-blue face, and a depressed emotion." 43 am I going to sit there" was my immediate thought. 44  then a deeper, quieter voice spoke, "Opportunity.”Finally I took my new seat and   45 that Kathy had been in an auto collision, and she was on her way for 46 。
When the snack of nuts and juice arrived, 47 did not take me long to realize that Kathy would not be able to 48 herself. I considered offering to feed her but 49 , as it seemed too close a service to offer to a stranger. But then I decided that Kathy's need was more important than my 50 . I offered to help her eat, and although she too was uncomfortable about __51___it, she did. The experience was   52 and she and I ___53__close in a short period of time. By the end of the five-hour trip, my heart was fully   54, and the time was __55___ better spent than if I had just sat by myself.
I was very glad I had reached beyond my comfort zone to sit next to Kathy and feed her. Love sometimes   56 beyond human borders and dissolves the fears   57  keep us separate. When we stretch to serve another, we grow to live in a larger, more 58 world.
Help me move   59 the small self so I can connect with the hearts of others.
When I give 60 to another, I feed my own soul.

D．comfortable

C．sightseeing

C．convenience