某导体两端电压为12V，通过的电流为0.8A，该导体的电阻为_______爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题填空题

某导体两端电压为12V，通过的电流为0.8A，该导体的电阻为______Ω；若导体两端的电压是18V，则通过的电流为______A，这时导体的电阻为______Ω．

答案

（1）根据欧姆定律可得：

导体的电阻R=

U

I

=

12V

0.8A

=15Ω；

（2）∵电阻是导体本身的一种特性，与电压和电流的大小无关，与材料、长度和横截面积有关，

∴电压为18V时，导体的电阻仍为15Ω，

通过导体的电流I′=

U′

R

=

18V

15Ω

=1.2A．

故答案为：15；1.2；15．

单项选择题 A1/A2型题

下列叙述中，属于残疾二级预防的是（）。

A.残疾不能通过单纯的临床治疗而痊愈

B.脑血管意外之后，定时翻身以避免发生压疮

C.从青少年开始运动锻炼，预防心脑血管疾病的发生

D.通过职业咨询和训练，促使残疾者重返家庭和社会

E.通过适应、代偿和替代的途径，提高患者生活自理和自立能力

完形填空

A few months ago, I was picking up the children at school. Emily, another mother that I knew well, rushed up to me. She was full of ____.
“Do you know ____ you and I are?” she asked. ____ I could answer, she gave out the reason for her question. She had just returned from renewing her driver’s license at a government office. The woman ____ desk asked her what her “occupation” was. Emily hesitated, ____ how to answer it. “What I mean is,” explained the woman, “do you have a job, or are you just a ...?” “Of course I have a job,” answered Emily. “I’m a (an) ____.” “We don’t ____ ‘mother’ as an occupation ... ‘housewife’ covers it,” she said.
I forgot all about her story ____ one day I found myself in the same situation. This time it was at our own Town Hall. The clerk was a woman.
“And what is your occupation?” she asked. What ____ me say it, I do not know. The words simply jumped out. “I’m ... a (an) ______ in the field of Child Development and Human Relations.”
The clerk stopped, her ball-point pen _____ in mid-air. She looked up ____ she had not heard right. I repeated the title slowly.
“Might I ask,” said the clerk with new interest, “just what you do in your _____?” Coolly, I heard myself _____, “I have a continuing program of research in the laboratory and in the field. I’m working for my masters (the whole family) and already have ____ credits (令人增光的人或事物) (all daughters). I often work 14 hours a day (24 is more like it). The job is more challenging than most jobs and the ____ are in satisfaction rather than just money.”
There was an increasing note of ____ in the clerk’s voice as she ____ in the form. As I drove into our driveway(私家车道), I was ____ by my lab assistants — ages 13, 7, and 3. Inside the house I could hear our new experimental model (six months) in the child-development program.
I felt successful. Motherhood...what a great ____.

B．even though