题干

实验桌上备有如下器材:符合实验要求的电源(电源电压不变)、已调零的电压表和电流表、电阻箱、滑动变阻器、开关各一个、导线若干.请你利用上述器材设计一个实验证明:电流不变时,电阻消耗的电功率 P 与电阻 R 成正比.要求:
上一题 下一题 0.0难度 选择题 更新时间:2012-05-07 03:14:21

答案(点此获取答案解析)

同类题2

阅读下面短文,从短文后面各题所给的四个选项(A、B、C和D中,选出可以填入空白处的最佳选项。

    The cultures of the East and the West really distinguish from each other a lot. This is because the culture systems are two 1 systems on the whole.

    The origin of the eastern culture is mainly from two countries: China and India. Both of the two cultures are gestated(孕育) by 2. In China, the mother river is the Yellow River, 3 the Indian one is the Hindu River. These two cultures have 4 for several thousand years and formed their own styles. Then in Tang Dynasty of China, the Chinese culture 5 went overseas to Japan, 6 into the Japanese society and 7 the Japanese culture nowadays. Though a bit different from the Chinese one, it 8 to the same cultural system.

    When the two mother rivers gave birth to the eastern culture, another famous culture was 9 on the Mesopotamian Plain(米索不达米亚平原): the Mesopotamian Civilization. This civilization later on developed into the cultures of the Ancient Greece and Ancient Rome. And these two are well-known as the 10 of the European culture. 11 the Chinese culture, the European one is also 12 to waters. When the colonists(殖民者) of England 13 in America, their culture went with them over the Atlantic Ocean. So the American culture doesn't 14 from the European one a lot.

    At the same time, the 15 of the language systems adds to the cultural differences. In the East, most languages belong to the pictographic(象形文字的) languages while the Western languages are 16 based on the Latin system, for example, the one I'm using to write this paper.

    Other factors like human race difference counts 17 . However, 18 the far distance and the steep areas between the East and West, the two cultures seldom 19 until recent centuries. 20 they grew up totally in their own ways with almost no interference from the other.