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MOOC 中国近现代史纲要(西安工程大学)1450293547 最新慕课完整章节测试答案

第一章近代中国的开端与中华民族伟大复兴任务之提出

第一章单元测试

1、单选题：
‍以下哪一项不是义和团运动的口号？（）‌
选项：
A: 扶清灭洋
B: 助清灭洋
C: 驱除鞑虏
D: 保清灭洋
答案: 【驱除鞑虏】点我阅读全文

发表于： 2021年10月5日 2021年10月5日
作者：站长
分类： mooc答案
标签： mooc, 慕课, 网课答案
发表评论: MOOC 中国近现代史纲要(西安工程大学)1450293547 最新慕课完整章节测试答案

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MOOC 英语(株洲市交通技工学校)1449963183 最新慕课完整章节测试答案

unit 1 Traditional festivals

1.2 The Spring Festival 单元测验

1、单选题：
‎People will put up ______(贴春联)on the door.
选项：
A: spring poems
B: New Year's Eve dinner
C: firecracker
D: red paper envelopes
答案: 【 spring poems】点我阅读全文

发表于： 2021年10月5日 2021年10月5日
作者：站长
分类： mooc答案
标签： mooc, 慕课, 网课答案
发表评论: MOOC 英语(株洲市交通技工学校)1449963183 最新慕课完整章节测试答案

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MOOC 政治学原理(太原理工大学)1450287365 最新慕课完整章节测试答案

第1讲政治的概念

第1讲单元测验

1、单选题：
根据视频，古今中外各种政治思潮最核心的区别在于对_______的概念的不同理解。 ‌‌
选项：
A: 人
B: 权力
C: 政治
D: 国家
答案: 【政治】点我阅读全文

发表于： 2021年10月5日 2021年10月5日
作者：站长
分类： mooc答案
标签： mooc, 慕课, 网课答案
发表评论: MOOC 政治学原理(太原理工大学)1450287365 最新慕课完整章节测试答案

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MOOC 英语阅读2(新余学院)1450727210 最新慕课完整章节测试答案

Lesson2

Scanning

1、单选题：
‌Read the passage "The Discovery of X-rays" quickly and choose the paragraph(s) which contain(s) the answer(s). You may choose more than one answer for question 3. ‌The Discovery of X-rays‌ Par. 1 Except for a brief description of the Compton effect, and a few other remarks, we have postponed the discussion of X-rays until the present chapter because it is particularly convenient to treat X-ray spectra after treating optical spectra. Although this ordering may have given the reader a distorted impression of the historical importance of X-rays, this impression will be corrected shortly as we describe the crucial role played by X-rays in the development of modern physics.Par. 2 X-rays were discovered in 1895 by Roentgen while studying the phenomena of gaseous discharge. Using a cathode ray tube with a high voltage of several tens of kilovolts, he noticed that salts of barium would fluoresce when brought near the tube, although nothing visible was emitted by the tube. This effect persisted when the tube was wrapped with a layer of black cardboard. Roentgen soon established that the agency responsible for the fluorescence originated at the point at which the stream of energetic electrons struck the glass wall of the tube. Because of its unknown nature, he gave this agency the name X-rays. He found that X-rays could manifest themselves by darkening wrapped photographic plates, discharging charged electroscopes, as well as by causing fluorescence in a number of different substances. He also found that X-rays can penetrate considerable thicknesses of materials of low atomic number, whereas substances of high atomic number are relatively opaque. Roentgen took the first steps in identifying the nature of X-rays by using a system of slits to show that (1) they travel in straight lines, and that (2) they are uncharged, because they are not deflected by electric or magnetic fields.Par. 3 The discovery of X-rays aroused the interest of all physicists, and many joined in the investigation of their properties. In 1899 Haga and Wind performed a single slit diffraction experiment with X-rays which showed that (3) X-rays are a wave motion phenomenon, and, from the size of the diffraction pattern, their wavelength could be estimated to be 10-8 cm. In 1906 Barkla proved that (4) the waves are transverse by showing that they can be polarized by scattering from many materials.Par. 4 There is, of course, no longer anything unknown about the nature of X-rays. They are electromagnetic radiation of exactly the same nature as visible light, except that their wavelength is several orders of magnitude shorter. This conclusion follows from comparing properties 1 through 4 with the similar properties of visible light, but it was actually postulated by Thomson several years before all these properties were known. Thomson argued that X-rays are electromagnetic radiation because such radiation would be expected to be emitted from the point at which the electrons strike the wall of a cathode ray tube. At this point, the electrons suffer very violent accelerations in coming to a stop and, according to classical electromagnetic theory, all accelerated charged particles emit electromagnetic radiations. We shall see later that this explanation of the production of X-rays is at least partially correct.Par. 5 In common with other electromagnetic radiations, X-rays exhibit particle-like aspects as well as wave-like aspects. The reader will recall that the Compton effect, which is one of the most convincing demonstrations of the existence of quanta, was originally observed with electromagnetic radiation in the X-ray region of wavelengths.‌‌When were X-rays discovered?
选项：
A: Par. 1
B: Par. 2
C: Par. 3
D: Par. 4
E: Par. 5
答案: 【 Par. 2】点我阅读全文