问题
问答题 简答题
为什么要在断电器触点旁并联一个电容器？
答案
参考答案：
在断电器触点旁并联一个电容器的原因是：在触点打开的瞬间，初级绕组中产生的自感电流与原电流方向相同，其电压高达300V左右，在断电器间产生强烈的火花。为了消除火花，故并联一个电容器
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为什么要在断电器触点旁并联一个电容器？
参考答案：
在断电器触点旁并联一个电容器的原因是：在触点打开的瞬间，初级绕组中产生的自感电流与原电流方向相同，其电压高达300V左右，在断电器间产生强烈的火花。为了消除火花，故并联一个电容器
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| It amazed me-every time I saw Joe he was smiling. It didn't matter whether he had to 1 at a stop light, or if he were the seventh person in 2 at the bank , and the teller closed her window just 3 he got there. Joe always smiled. It made me wonder why he always seemed so 4 . Having observed Joe with other people, I also noticed something else. Joe 5 people how they were doing, and really seemed to listen to their answers. He was 6 if someone was hurt , and had kind words, and 7 to help in any way he could. It made me think… what if I tried to smile more? An 8 of sorts began when I went to a grocery store. I 9 as I went up and down the aisles (过道)... and people I didn't even 10 smiled back at me. Some even 11 ! The little kid in the cart who was giving his mother a 12 time saw me smile and stopped talking…and, you guessed it-he made a little 13 attempt at a smile. The man in the handicapped cart 14 a person to reach something… I could get that for him. The smile even 15 to him, and he thanked me and smiled at me. As I 16 home, I was smiling. I thought about what I had just 17 , and when someone passed my car and gave me a gesture, I smiled at him. He looked 18 . Now I know a smile is a 19 thing, but what if we were all to try to smile a few more times each day? I couldn't believe how great I felt. 20 in my life had changed-but maybe it had. For what I learned was that such a small thing could lift not only my spirits, but those around me as well. | ||||
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