慕课标签存档

泵送主系统常见故障诊断与排除

主系统故障

1、单选题：
‎一根弯曲半径为1m的φ125mm的直角弯管的阻力相当于（       ）‏‎‏
选项：
A: A、水平3m直管；
B: B、水平6m直管；
C: C、水平9m直管
D: C、水平12m直管
答案: 【 C、水平9m直管】点我阅读全文

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第六章常用表达方法

第六章测试（新）

1、单选题：
‍机件向不平行于任何基本投影面的平面投射所得的视图叫（ ）‏
选项：
A: 局部视图
B: 斜视图
C: 基本视图
D: 向视图
答案: 【 斜视图】点我阅读全文

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第1章 中华武术的厉史

第1章 中华武术的厉史 单元测验

1、单选题：
‌殷商时期，出现武术训练的重要手段是‌
选项：
A: 打猎
B: 狩猎
C: 田猎
D: 田围
答案: 【 田猎】点我阅读全文

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项目一智能建筑的认识

智能建筑的认识

1、单选题：
下列选项中（  ）不属于建筑智能化工程。‍​‍
选项：
A: 通信网络系统
B: 接地系统
C: 综合布线系统
D: 住宅（小区）智能化系统
答案: 【 接地系统】点我阅读全文

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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

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第二章专家控制

章测试题

1、单选题：
​专家控制的特点不包括‏​‏
选项：
A: 灵活性
B: 适应性
C: 鲁棒性
D: 网络结构
答案: 【 网络结构】点我阅读全文

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Chapter10DesigningAndManagingIntegratedMarketingChannels

Chapter10DesigningandManagingIntegratedMarketingChannels

1、单选题：
‍ ________ are sets of interdependent organizations participating in the process of making a product or service available for use or consumption.‎‍‎
选项：
A: Marketing channels
B:  Interstitials
C:  Communication channels
D:  Sales territories
E:  Marketing terrains
答案: 【 Marketing channels】点我阅读全文

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实验一A数字电路仪器使用仪器使用与测试方法研究

1.1随堂测验

1、单选题：
​Run/Stop按键红灯亮时，示波器处于       运行状态。‍
选项：
A: 连续
B: 停止
C: 运行
D: 出错                                                                                                                                                                                                        
答案: 【 停止】点我阅读全文

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第一章引言

1.1软件的概念随堂测验

1、单选题：
​Software doesn't include _____.‎
选项：
A: data
B: CPU
C: manual
D: contract
答案: 【 CPU】点我阅读全文

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第一章管理会计思维上

1.1管理会计思维管理者看报表随堂测验

1、单选题：
‏1.管理会计的基本职能不包括下列哪项（）。‌
选项：
A: 参与经济决策
B:  规划经济目标
C: 完成会计记录
D: 考核经营业绩
答案: 【 完成会计记录】点我阅读全文

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