2007年诺贝尔物理学奖授予了两位发现“巨磁电阻”效应的物理学家。某探究小组查到

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问题:

2007年诺贝尔物理学奖授予了两位发现“巨磁电阻”效应的物理学家。某探究小组查到某磁敏电阻在室温下的电阻随磁感应强度变化曲线如图甲所示,其中R、R0分别表示有、无磁场时磁敏电阻的阻值。为研究其磁敏特性设计了图乙所示电路.关于这个探究实验,下列说法中正确的是(    )

A.闭合开关S,图乙中只增加磁感应强度的大小时,伏特表的示数增大

B.闭合开关S,图乙中只改变磁场方向原来方向相反时,伏特表的示数减小

C.闭合开关S,图乙中只增加磁感应强度的大小时,流过ap段的电流可能减小

D.闭合开关S,图乙中只增加磁感应强度的大小时,电源的输出功率可能增大

考点:闭合电路欧姆定律
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春秋争霸战争与战国兼并战争都为统一打下了基础。

错误:____________

改正:____________

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关于人体的能量储备和需要,下列哪项不正确()

A.机体消耗脂肪时,蛋白质的氧化供能停止

B.饥饿时消耗脂肪供能,对组织器官的功能影响不大

C.糖原的含量有限,只占一天正常需要量的1/2

D.蛋白质作为能源会使器官功能受损

E.机体的能量储备包括糖原、蛋白质、脂肪

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某人沿电车路行走,每12分钟有一辆电车从后面追上,每4分钟有一辆电车迎面开来,假定此人和电车都是匀速前进,则电车是每隔几分钟从起点站开出一辆

A.4

B.6

C.8

D.10

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It is over 40 years since first atomic bomb was dropped on a major city in Japan. Yet even now its effects are showing themselves and may continue to do so for years to come. Much effort and human energy have been used to try to prevent such a terrifying thing from happening again. So far there is no guarantee that it will not. Countries which already possess nuclear knowledge and resources have bombs stored away which are powerful enough to wipe out all life on earth. But this is not all. Other countries, which previously were not so advanced in technology, are gradually buying materials that can be used for making atomic devices. This nuclear energy will naturally be of great value in helping the economy of poorer nations.

The generation of electricity through nuclear power came directly from the original work on the atom bomb. Because of the increase in demand for energy and the possibility of decreasing supplies of oil and natural gas, the interest in electricity has increased. One of the by-products of nuclear power stations is plutonium (钸) produced from unclear fuel: plutonium is ingredient (成分) in bomb-making. It means that there are far more opportunities for the manufacture of bombs.

This brings the problem to a full circle again. How can something so valuable and useful be controlled so that it works for the benefit and not the destruction of man?

9. The effects of dropping the first atomic bomb ________.

A. are not over                    B. may go on forever    

C. could last much longer            D. will not be over in the near future

10. The writer says that enough atomic bombs have already been manufactured to ________.

A. wipe out Japan                  B. last forever    

C. act as a peace-keeping device      D. destroy all living things

11. The advantage of less developed countries being able to make atomic devices is that it ______.

A. gives them more opportunities for work     B. will help poor countries to become richer

C. will enable them to make better explosives   D. will be of great value to them

12. The second paragraph tells us that the increased demand for electricity today ________.

A. has led to the decrease in supplies of oil

B. means that more countries are interested in nuclear power

C. has increased the risk of accidental explosions

D. has increased the very means of producing more atomic bombs

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下列药物中,具有利尿作用的是( )。

A.氢氯噻嗪

B.氯贝丁酯

C.螺内酯

D.依他尼酸

E.特布他林

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