放大电路为何一定要加直流电源?

题型:问答题 简答题

问题:

放大电路为何一定要加直流电源?

考点:电厂电气专业继电保护技能鉴定考试电厂电气专业继电保护技能鉴定考试题库
题型:问答题 简答题

Would you completely trust your friends if you couldn’t see anything? If you are falling, do you believe they will catch you and help you stand up? Our teacher helped us to find the answer.

Our teacher is named Morrie. One day, he said that he had a game for us to try. He divided us into two groups. One of the students from the first group, stands in front of us with his eyes closed, and then falls backwards(向后). The second group stand behind him. Before he falls on the floor, they should catch him and not let him get hurt. Most of us were uncomfortable with this. We were afraid that they wouldn’t catch us and we would hit the floor. So we didn’t move. We just stood there and laughed in embarrassment(尴尬).

Finally, one student, thin, quiet, dark-haired girl called Sarah, decided to move. She crossed her arms in front of her body, closed her eyes, and slowly fell backwards. She looked quiet but brave.

For a moment, I was sure she was going to fall on the floor. But before she hit the floor, the other students caught her, held her and finally helped her stand up.

“Whoa!!” we were all surprised, and also encouraged. The girl was happy, too. Seeing this, Morrie smiled and said to the girl, “When you close your eyes, you can’t see anything. You won’t feel safe. When you are falling, the feeling gets stronger. You are not sure whether you will hit the cold, hard floor or the warm, soft hands of your friends. But if you are brave enough to trust them, they won’t let you down.”

小题1:According to the passage, we can know Morrie is ___________.

A.a student

B.a teacher

C.a manager

D.a farmer小题2:The writer thought the girl was ___________.

A.strong but shy

B.active

C.quiet but brave

D.careless小题3:In the end, the girl ___________.

A.got hurt

B.fell on the floor

C.was only helped by the writer

D.was caught by the other students小题4:The students felt encouraged because ___________.

A.they could stop the game finally

B.they wanted to do something else

C.they thought they had won the game

D.they felt that they could trust each other

题型:问答题 简答题

设关于x的一次函数y=a1x+b1与y=a2x+b2,则称函数y=m(a1x+b1)+n(a2x+b2)(其中m+n=1)为此两个函数的生成函数.

(1)当x=1时,求函数y=x+1与y=2x的生成函数的值;

(2)若函数y=a1x+b1与y=a2x+b2的图象的交点为P,判断点P是否在此两个函数的生成函数的图象上,并说明理由.

题型:问答题 简答题

股骨颈骨折可能发生()

A.动、静脉损伤

B.周围神经损伤

C."方肩"畸形

D.缺血性骨坏死

E.损伤性骨化

题型:问答题 简答题

面砖排列的形式分别为()、()和密缝、疏缝四种。

题型:问答题 简答题

下列内存中,与地址线无关的内存是()

A.扩展内存

B.扩充内存

C.常规内存

D.上位内存

更多题库