问题 实验题

现有一个可以显示通过自身电流的电阻器Rg,其允许通过的最大电流为1mA,阻值约为几百欧。另外还提供以下器材:量程为0~10V的电压表、阻值为7500Ω的定值电阻R0、电压可调的电源、开关各一只,导线若干。为了测出这一电阻器Rg的阻值,甲、乙两同学分别设计了如下两个电路:

(1)你认为应选用               电路(选填“甲”或“乙”);

(2)选用了正确的电路后,得到下表中的四组数据,请根据表中数据在坐标纸上作出U-I图象;

      

(3)根据图象可求得Rg的阻值为                        Ω。

答案

(1)乙

(2)

(3)500

单项选择题 A2型题
单项选择题

Should anyone much care whether an American boy living overseas gets six vicious thwacks on his backside So much has been argued, rejoined and rehashed about the case of Michael Fay, an 18-year-old convicted of vandalism and sentenced to a caning in Singapore, that an otherwise sorry little episode has shaded into a certified International Incident, complete with intercessions by the U. S. head of state. An affair has outraged American libertarians even as it has animated a general debate about morality East and West and the proper functioning of U.S. law and order.

Which, to all appearances, is what Singapore wanted. The question of whether anyone should care about Michael Fay is idle. though Singapore officials profess shock at the attention his case had drawn, they know Americans care deeply about the many sides of this issue. Does a teenager convicted of spraying cars with easily removable paint deserve half a dozen powerful strokes At what point does swift, sure punishment become torture By what moral authority can America, with its high rates of lawlessness and license, preach of a safe society about human rights

The caning sentence has concentrated minds wondrously on an already lively domestic debate over what constitutes a due balance between individual and majority rights. Too bad Michael Fay has become a focus for this discussion. Not only does he seem destined to be pummeled and immobilized, but the use of Singapore as a standard for judging any other society, let alone the cacophonous U. S. , is fairly worthless.

To begin with, Singapore is an offshore republic that tightly limits immigration. Imagine crime-ridden Los Angeles, to which Singapore is sometimes contrasted, with hardly any inflow of the hard-luck, often desperate fortune seekers who flock to big cities. Even without its government’s disciplinary measures, Singapore more than plausibly would be much the same as it is now. An academic commonplace today is that the major factor determining social peace and prosperity is culture--a sense of common identity, tradition and values.

Unlike Singapore, though, the U. S. today is a nation in search of a common culture, trying to be a universal society that assimilates the traditions of people from all over the world. Efforts to safeguard minority as well as individual rights have produced a gridlock in the justice system. Its troubles stem more from the decay of family life than from any government failures. Few societies can afford to look on complacently. As travel eases and cultures intermix, the American experience is becoming the world’s.

The circumstances of this affair--evidently no Singaporean has ever been punished under the Vandalism Act for defacing private property--suggest that Singapore has used Fay as an unwilling point man in a growing quarrel between East and West about human rights.

The word "cacophonous" (Para. 3) most probably means()

A. commonplace

B. assimilative

C. disharmonious

D. stereotyped