慕课标签存档订阅

第二章 几何组成分析 单元测试题

1、单选题：
‌平面内联结四个刚片的复铰结点，其约束个数为：（   ）‌
选项：
A: 2
B: 4
C: 6
D: 8
答案: 【 6】点我阅读全文

第二章课后测试·

1、单选题：

‎

‎选项：
A: A
B: B
C: C
D: D
答案: 【 B】点我阅读全文

第一章测试

1、单选题：
‏在组织工艺流程时，应遵循的原则之一是：尽可能：‏‏‏
选项：
A: 提高原料的转化率 
B: 降低主产品的选择性
C: 未反应的原料无需循环利用
D: 降低原料的收率
E: 提高产品的收率
F: 降低原料的转化率
答案: 【 提高产品的收率】点我阅读全文

单元测试

1、判断题：
​钢结构设计可以不遵守行业规范​
选项：
A: 正确
B: 错误
答案: 【 错误】点我阅读全文

工程经济学概论测试题

1、单选题：
‏工程经济学是运用（ ）有关知识相互交融而形成的工程经济分析原理与方法，是为实现正确的投资决策提供科学依据的一门应用性经济学科。‌
选项：
A: 工程学
B: 经济学
C: 工程学和经济学
D: 工程经济学
答案: 【 工程学和经济学】点我阅读全文

绪论单元测试

1、单选题：
‏在大体解剖学的研究中，需要借助的观察仪器是​
选项：
A: 不需要仪器，肉眼观察
B: 光学显微镜
C: 透射电镜 
D: 扫描电镜
答案: 【 不需要仪器，肉眼观察】点我阅读全文

绪论部分测试

1、判断题：
​对于基于金属应变片的柱式力传感器，由于钢柱能够将力转换为钢柱的形变，因此，钢柱是转换元件。‌
选项：
A: 正确
B: 错误
答案: 【 错误】点我阅读全文

实际工作中的成本开支范围与理论成本包括的内容是。

1、单选题：
​实际工作中的成本开支范围与理论成本包括的内容是      。‎
选项：
A: 有一差别的
B: 完全一致的
C: 两个不同概念
D: 可以相互替代
答案: 【 有一差别的】点我阅读全文

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

单元测验

1、单选题：
‏关于信息社会，下列说法不正确的是(   )‍
选项：
A: 计算机的发明和广泛使用是人类社会进入信息社会的唯一标志。
B: 信息社会中所有的工业生产都是自动化的。
C: 在信息社会，信息技术催生大批新兴产业，同时，传统产业也普遍实行技术改造。
D: 信息社会中信息产业高度发展，在产业结构优势的地位日益突出。
E: 在信息社会，信息、知识成为重要的生产力要素。
F: 信息社会是从20世纪中叶开始的，又称后工业社会。
G: 计算机的发明是第三次科技革命的重要标志，是人类文明史上继蒸汽技术革命和电力技术革命之后科技领域里的又一次重大飞跃。
答案: 【 计算机的发明和广泛使用是人类社会进入信息社会的唯一标志。;
信息社会中所有的工业生产都是自动化的。】点我阅读全文