某导体接到由两节新的干电池串联组成的电源两端，通过它的电流是_爱下问搜题

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问题填空题

某导体接到由两节新的干电池串联组成的电源两端，通过它的电流是0.3安，则20秒钟内通过该导体横截面积的电荷量是库，此时该导体的阻值是欧；当该导体两端不接电源时，它的阻值是欧。

答案

6； 10； 10

通过该导体横截面积的电量是Q=It=0.3A×20s=6C；

由欧姆定律可得：R=U/I=3/0.3=10Ω；

因导体的电阻为导体本身的性质和导体两端的电压无关，故当电压为0时，电阻仍为10Ω；

故答案为：6；10；10．

完形填空

阅读下面短文，掌握其大意，从每题所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。
It was a dark day, one of depression, sorrow and anger. As I climbed out of the   36   , after witnessing my time in the 100 yard freestyle, I did not feel like speaking to anyone. I saw the bright smiles of swimmers who had just   37 a best time.   38   , I had failed. Or at least that is what I thought at the time.
I was lying on my cool bed when an idea   39  me. Success is the   40  to go from failure to failure without losing your   41  . At practice the next day, I told my swimming teammates about my goal time and they all either laughed or replied with a   42  similar response like, “You can’t do it” or “Probably not”. Believe it or not, these are the responses that make my goal   43 .
Finally came the day when I had to   44  to myself and others that with     45    there is no limit to your achievements.
With the starting gun   46  , I dived with perfect form into the pool. I felt the cool water running   47  my back. I swam like a fish, bouncing off each    48   at the wall as if it was a spring board. On the   49  turn, I came back to the wall with every piece of strength I had. I   50  the final wall with my fingertips and I knew that I had swum the   51  race.
I had done it! I had achieved my best time! Joy filled my   52  like water does a cup. I saw the   53  on all of my friend’s face as I   54  out of the pool; their jaws dropped to the ground. I began to laugh and gave them the thumbs up.
I have   55  in life that having belief in yourself opens all gates. Never forget that anything the mind can conceive and believe it can achieve.

A．opportunity

A．consideration

A．setting out

C．breaking out

D．getting off

A．expressions

多项选择题

采用工程量清单计价模式时，不得作为竞争性费用的有（）。

A.安全文明施工费

B.其他项目费

C.规费

D.税金

E.风险费用