某学习小组探究电学元件的伏安特性曲线。 ①甲同学要描绘一个标有“3.6V,1.2

题型:实验题

问题:

某学习小组探究电学元件的伏安特性曲线。

①甲同学要描绘一个标有“3.6V,1.2W”的小灯泡的伏安特性曲线,除了导线和开关外,还有下列器材可供选择:

电压表V(量程5V,内阻约为5kΩ)

直流电源E(电动势4.5V,内阻不计)

电流表A1(量程350mA,内阻约为1Ω)

电流表A2(量程150mA,内阻约为2Ω)

滑动变阻器R1(阻值0 ~ 200Ω)

滑动变阻器R2(阻值0 ~ 10Ω)

实验中电流表应选______,滑动变阻器应选______;(填写器材代号)

以下的四个电路中应选用_________进行实验。

②乙同学利用甲同学的电路分别描绘了三个电学元件的伏安特性曲线,如图所示。然后他用图所示的电路给三个元件分别供电,并测出给元件1和元件2供电时的电流和电压值,分别标在图上,它们是A点和B点。已知R0=9.0Ω,则该电源的电动势_______V,内电阻_______Ω。这个电源给元件3供电时,元件3的电功率P=_______W。

考点:实验:伏安法测电阻实验:练习使用示波器实验:测绘小灯泡的伏安特性曲线实验:探究影响导体电阻的因素
题型:实验题

       ①课外阅读是提高语文水平的重要途径,可以使我们获得很多有益的启示,充实我们的生活。②读《三国演义》,我们可以领略到诸葛亮舌战群的风采;③读《钢铁是怎样练成的》,我们能领悟到人生的真谛和生命的意义;                                                                                                      

①第②句中,加横线字“儒”的读音为:                              

②第③句中,有一个错别字,它是:              ,应改为:             

③第③句中,加横线词“真谛”的含义是:                                                                 

④仿照划线句子的句式,再仿写一组句子。

                                                                                                                                     

题型:实验题

2014年1月10日,2013年度国家科学技术奖励大会在北京人民大会堂隆重举行。国家 * * 向获得2013年度国家最高科学技术奖的两位中国科学院院士                  、

                  颁奖。听着主持人介绍两位科学家的突出贡献,同时又看到很多人都以崇敬的目光看着颁奖台上的两位科学家,张华由衷地感叹:“我以后也要争当科技之星!”

(1)请完成材料横线处内容填写。(2分)

(2)张华为什么要争当科技之星?(4分)

(3)想要实现这一愿望,张华应该怎么做?(两方面即可,4分)

题型:实验题

1964年10月,我国取得重大科研成果是

A.第一颗原子弹试爆成功

B.第一枚近程导弹发射成功

C.第一颗人造地球卫星发射成功

D.第一颗氢弹试爆成功

题型:实验题

协会以外主体做出的、符合相关规定条件的奖励信息,会员应自收到对本单位及本单位从业人员奖励决定文书之日起()个工作日内向协会诚信管理系统申报,协会审核后记入诚信信息系统。

A.5

B.7

C.10

D.15

题型:实验题

If you smoke, you’d better hurry. From July 1st pubs all over England will, by law, be no-smoking areas. So will restaurants, offices and even company cars, if more than one per-son uses them. England’s smokers are following a well-trodden path. The other three bits of the United Kingdom have already banned smoking in almost all enclosed public spaces, and there are anti-smoking laws of varying strictness over most of Western Europe. The smoker’ s journey from glamour through toleration to suspicion is finally reaching its end in pariah status.

But behind this public-health success story lies a darker tale. Poorer people are much more likely to smoke than richer ones—a change from the 1950s, when professionals and la-borers were equally keen. Today only 15% of men in the highest professional classes smoke, but 42% of unskilled workers do. Despite punitive taxation—20 cigarettes cost around £ 5.00 ($10.00), three-quarters of which is tax—55% of single mothers on benefits smoke. The figure for homeless men is even higher; for hard-drug users it is practically 100% . The message that smoking kills has been heard, it seems, but not by all.

Having defeated the big killers of the past—want, exposure, poor sanitation—governments all over the developed world are turning their attention to diseases that stem mostly from how individuals choose to live their lives. But the same deafness afflicts the same people when they are ply encouraged to give up other sorts of unhealthy behavior. The lower down they are on practically any pecking order—job prestige, income, education, background-the more likely people are to be fat and unfit, and to drink too much.

That tempts governments to shout ever louder in an attempt to get the public to listen and nowhere do they do so more aggressively than in Britain. One reason is that pecking orders matter more than in most other rich countries: income distribution is very unequal and the unemployed, disaffected, ill-educated rump is comparatively large. Another reason is the frustration of a government addicted to targets, which often aim not only to improve some-thing but to lessen inequality in the process. A third is that the National Health Service is free to patients, and paying for those who have arguably brought their ill-health on themselves grows alarmingly costly.

Britain’ s aggressiveness, however, may be pointless, even counter-productive. There is no reason to believe that those who ignore measured voices will listen to shouting. It irritates the majority who are already behaving responsibly, and it may also undermine all government pronouncements on health by convincing people that they have an ultra-cautious margin of error built in.

Such hectoring may also be missing the root cause of the problem. According to Mr. Marmot, who cites research on groups as diverse as baboons in captivity, British civil servants and Oscar nominees, the higher rates of ill health among those in more modest walks of life can be attributed to what he calls the "status syndrome". People in privileged positions think they are worth the effort of behaving healthily, and find the will-power to do so. The implication is that it is easier to improve a person’s health by weakening the connection between social position and health than by targeting behavior directly. Some public-health experts speak of social cohesion, support for families and better education for all. These are bigger undertakings than a bossy campaign; but more effective, and quieter.

The word "pariah" (line 5, paragraph 1) is closest in meaning to()

A. prohibition

B. strictness

C. pardon

D. punishment

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