mooc答案类别订阅

z变换与拉普拉斯变换的关系

1、单选题：

‌已知，则其在Z域的表达式为（）。

​

‌

​选项：
A:

B:

C:

D:

答案: 【 

】点我阅读全文

单元测验1-地基模型

1、单选题：
‏文克勒地基模型是属于（  ‍）。‍
选项：
A: ‍线弹性地基模型
B: 半塑性地基模型
C: 半无限地基模型
D: 非线性弹性模型
答案: 【 ‍线弹性地基模型】点我阅读全文

第一周单元测试

1、单选题：
‍通过下列那个工具栏可快速还原到AUTOCAD经典工作空间（  ）。​
选项：
A: 标准工具栏
B: 特性工具栏
C: 工作空间工具栏
D: 样式工具栏工具栏
答案: 【 工作空间工具栏】点我阅读全文

电力系统概论

1、单选题：

‏发电机的额定电压为（         )。

​

‏

​选项：
A: 6kV
B: 6.3kV
C: 6.6kV
D: 6.15kV
答案: 【 6.3kV】点我阅读全文

不定积分的分部积分法测试

1、单选题：

‍

‍选项：
A:
B:
C:
D:
答案: 【 】点我阅读全文

第1讲-小测验

1、单选题：
‌以下各语言书写的代码可认为其功能是相同的。对于该代码，哪项判断是正确的？‌‌C/C++：‌‌#include <stdio.h>‌‌int hehe(){‌‌    printf("hehe");‌‌    hehe();‌‌    return 0;‌‌}‌‌int main(){‌‌    hehe();‌‌    return 0;‌‌}‌‌‌‌Java语言：‌‌public class Main{‌‌ public static int hehe() {‌‌ System.out.println("hehe");‌‌                hehe();‌‌ return 0;‌‌ }‌‌ public static void main(String args[])‌‌    {‌‌ hehe();‌‌    }‌‌}‌‌‌‌Python语言：‌‌def hehe():‌‌    print("hehe")‌‌    hehe()‌‌    return 0‌‌‌‌‌‌hehe()‌‌‌
选项：
A: 代码有错，无法运行。
B: 代码可以运行，并在有限次函数调用后结束。
C: 代码可以运行，将产生无限次函数递归调用（不考虑机器出故障、停电等意外因素）。
D: 以上都不对。
答案: 【 代码可以运行，并在有限次函数调用后结束。】点我阅读全文

第一章单元测验

1、单选题：
‏发电厂的主要作用是：‍
选项：
A: 能量转换
B: 产生合格的电能
C: 加热给水
D: 提高国民经济
答案: 【 产生合格的电能】点我阅读全文

第十章测试

1、单选题：
‌“受欢迎的影片——更确切的说是受欢迎的银幕母题——应该满足现有的大众欲望”，这句话来自‍
选项：
A: 克拉考尔
B: 埃德加·赖茨
C: 汉斯·德普
D: 赫尔曼·伦斯
答案: 【 克拉考尔】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

单元测试一

1、单选题：
​芭蕾形体是培养学生综合能力和塑造其形体动作的状态，提高灵活性、（             ）性、从而达到优美体态的一门基础课。‌
选项：
A: 力量
B: 协调
C: 稳定
D: 柔软
答案: 【 协调】点我阅读全文