1、a:3:i:0;s:10754:外语教学与研究出版社高中英语必修3Module4综合能力练习#必修3 Module4 综合能力练习#第一部分：#听力（略）#第二部分：#英语知识运用（共两节，满分45分）#第一节 单项填空（共15小题；# 每小题1分，满分15分）#21. As it is getting close to the Spring Festival, the _ in the street becomes more and more delightful.# A. air B. atmosphere C. environment D. surrounding #22. Must I
2、 fetch the book for you now?# No, you neednt. Its not _. I can wait till tomorrow. #A. anxious B. instant C. hurried D. urgent #23. If you want help money or anything, let me know, _ you?# A. dont B. will C. shall D. do #24. New ways have been found to prevent the river _.# A. not to be polluted B.
3、against polluting# C. from polluting D. from being polluted#25. She _ her notes before the examination and tried to recite some important points. #A. looked for B. looked up C. looked through D. looked into #26. When I saw her, she was giving _ books to the children in the classroom.# A. off B. up C
4、. away D. out #27. They pushed with all their _, but the car didnt move even a stones throw.# A. strength B. force C. power D. right #28. Have you any letters _?# No, thanks.# A. to type B. to be typed# C. to be typing D. typed#29. Why didnt you arrive yesterday?# Oh, sorry. We _ the fog and the pla
5、ne was delayed.# A. were caught on B. were caught in C. caught in D. caught on #30. Cant you see youre not leaving enough space?# Go away!# You have no rights to force me!# I wont do it!# _ no!# A. In all B. After all C. In a nutshell D. For short #31. Our school basketball team is going to _ some n
6、ew players, so we hope you sign your names on the list if you are interested.# A. take in B. draw on C. give in D. bring out #32. The workers do nothing but _ tea and talk to each other.# A. drink B. to drink C. drinking D. are drinking #33. Why are you driving so slowly?# _. I cant see anything. Th
7、eres sand everywhere.# A. I have no idea B. It couldnt be worse #C. Its extremely serious D. I think youre absolutely right #34. Was it _ she said or something that she did _ you were angry at so much?# A. what;# that B. that;# which C. that;# what D. what;# which #35. Tom is said _ a new machine fo
8、r our company, but I dont know when he will finish it.#A. to design B. to be designing #C. to have been designing D. to have designed#第二节 完形填空（共20小题；#每小题1.5分，满分30分）#阅读下面短文，掌握其大意，然后从3655各题所给的A、B、C和D四个选项中，选出可以填入空白处的最佳选项。#Have you seen a sandstorm?# I would like to share with you my personal _36_ of th
9、e sandstorm in northern China. On April 7, 2004, we decided to _37_ a city of Jilin Province. It was supposed to be four hours drive from the place where we lived. We _38_ at about 7:#00 only to see the most amazing _39_ we had ever seen. The sky was _40_ as if it was midnight. The _41_ from the few
10、 cars that dared travel in the streets were yellowish. So we had to stay at home, _42_ for a better condition for our trip.#The wind was fairly _43_ and might have been stronger at night _44_ we woke up. The visibility（能见度） at this point was close to 20 m. About two hours later the _45_ increased to
11、 50 m and stayed so 46 about 10:#00 am. #When the dust lifted（消散） a little and the visibility _47_ to 200 m, we decided to drive out. However, everybody on the road was enveloped in thick frog with dust and the sky glowed with a dark _48_ color, so we hardly see each other _49_. Sometimes, the wind
12、suddenly _50_ up a lot of dust and sand and the visibility occasionally decreased to 20-50 m, making it very _51_ to drive.# The dust _52_ in the air until the late afternoon when it slightly lifted. At last, we arrived at the city, but the trip that _53_ took about four hour, took us nearly eight h
13、ours. The dust remained in the _54_ for about two more days. On the third day a short period of rain _55_ as the cold front passed the region. So the terrible scene came to an end, and everything took on a lively and fresh appearance again. #36. A. experience B. record C. idea D. action #37. A. leav
14、e B. visit C. call D. see#38. A. woke up B. sat up # C. set off D. left off #39. A. storm B. snow C. rain D. wind#40. A. dark B. bright C. blue D. cold#41. A. walls B. glass C. covers D. lights#42. A. leaving B. waiting C. taking D. calling #43. A. strong B. faint C. weak D. soft#44. A. after B. whe
15、n C. before D. while#45. A. speed B. power C. strength D. visibility#46. A. since B. before C. when D. until#47. A. increased B. reduced C. decreased D. stayed#48. A. red B. yellow C. green D. black#49. A. faintly B. clearly C. successfully D. perfectly#50. A. picked B. took C. turned D. looked #51.
16、 A. safe B. dangerous C. normal D. likely #52. A. remained B. jumped C. covered D. dropped #53. A. normally B. rarely C. frequently D. particularly#54.#A. city B. town C. air D. car#55. A. happened B. dropped C. struck D. flew #第三部分：#阅读理解（共10小题；#每小题2分，满分20分）#阅读下列短文，从每题所给的A、B、C和D四个选项中选出最佳选项。# A #A gr
17、eat king of a land far away in the East had a daughter. She was very beautiful, but so conceited that she thought nobody was as beautiful and rich as her. Every day, she only idled away by playing with her servants in the garden. Moreover, she thought that none of the princes who wanted to marry her
18、 was good enough. All she ever did was make fun of them. The old king was very angry, so he decided whether she was willing or unwilling, she would marry the first man that came to their kingdom. #Two days later a traveling pianist came to the castle. He began to play under the window and begged for
19、 money. And he was brought in. When he had sung before the king and the princess, he begged for a gift. The king said, “You have sung so well that I will give you my daughter as your wife.” The princess begged and prayed, but the king said, “ I will keep my word.” Words and tears were useless, and s
20、he was married to the poor pianist. #But this wasnt the end of the story. Being the wife of a poor pianist, the once proud prince had to busy herself with lots of housework. She gradually became admirable woman capable of whatever a woman should do. She also became gentle and warm-hearted, always re
21、ady to help others. But one day, beyond her expectation, her husband told her he was actually a prince of a wealthy kingdom. He pretended to be a poor man and married her, only because he wanted to let her know, life was not that easy. Everybody, no matter a common folk or an honorable noble, should
22、 work hard to earn their own bread. #56. The underlined word “conceited” probably means _. #A. proud B. beautiful C. polite D. graceful#57. Which of the following statements is TRUE according to the passage?# #A. The poor pianist treated his wife badly and the king was very angry. #B. The princess w
23、as a proud and lazy girl when she was in her kingdom. #C. The old king was satisfied with what his daughter had done.#D. The king would marry his daughter to a man who first treated her well.#58. The rich prince pretended to be a poor pianist, because _.#A. he wanted to ask for much more money form
24、the king#B. he was tired of his rich life and wanted to have a change#C. he wanted to make his wife learn life was difficult#D. he wanted to make fun of his wife and made her happy# B#Because of the development of agriculture, the area of land affected by sand has gradually increased. During the 195
25、0s and 1960s the land affected by sand expanded on average into 1,600 square kilometers per year. By the 1990s, the area had reached 2,500 square kilometers per year.# This kind of situation is particularly serious in many regions upwind（逆风的） from Beijing. Fengning City in Hebei Province and Duolun
26、City in Inner Mongolia lie to the north of Beijing, and in the last 50 years the population of these two cities has grown by 2 to 3 times. In order to obtain more resources, the inhabitants have been busy with heavy farming, tree-cutting and keeping animals. The result is that the soil which has sus
27、tained damage, and the sand layer below the earth is now exposed on the ground and the ground is rapidly being controlled by the spread of sand. #China has already noticed this problem, and has take measures to save the land. Nowadays, some land used for farming has returned to forestland and grassl
28、and. The Chinese government announced that it would invest more than RMB 600,000,000 to control Beijings sandstorms in the coming years. Only by decreasing the damage caused by man and restoring the natural environment will it be possible to well control the sources of the sand and dust. We hope in
29、the not-distant future, we will solve the problem successfully and effectively. #59. Compared with 50s and 60s, the land affected by sand increased by _ square kilometers by the 1990s.#A. 1,600 B. 2,500 #C. 900 D. 1,100 #60. Which of the following is NOT the cause of the damaged land?# #A. People us
30、e the resources too much.#B. People keep animals which need more grain.#C. People prepare too much land to grow crops.#D. People cut a lot of forests and raise animals.#61. The major measure that Chinese government has taken is _. #A. controlling the growth of the population #B. making better use of
31、 natural resources #C. killing fewer animals and cutting fewer trees #D. returning some land to forestland and grassland#62. According to the passage, it can be inferred that _ was the major factor of the environmental damage.#A. man B. animal C. nature D. desert # C #Paying attention to someone in
32、a conversation is called “attending” . It means that your ears, your eyes, your body and your feelings are all focused on that person at the time. Attending includes:# #Physical Presence. Friendships are a building process. You and your friend gradually share interests, feelings and goals. Much of t
33、his is done by being together physically. Your physical presence shows that you care about your friend. It mean;i:1;s:27074:完整版传感器与检测技术习题答案#第1章 传感器与检测技术基础思考题答案#l.检测系统由哪几部分组成?# 说明各部分的作用。#答：#一个完整的检测系统或检测装置通常是由传感器、测量电路和显示记录装置等几部分组成，分别完成信息获取、转换、显示和处理等功能。#当然其中还包括电源和传输通道等不可缺少的部分。#下图给出了检测系统的组成框图。#检测系统的组成框图
34、#传感器是把被测量转换成电学量的装置，显然，传感器是检测系统与被测对象直接发生联系的部件，是检测系统最重要的环节，检测系统获取信息的质量往往是由传感器的性能确定的，因为检测系统的其它环节无法添加新的检测信息并且不易消除传感器所引入的误差。#测量电路的作用是将传感器的输出信号转换成易于测量的电压或电流信号。#通常传感器输出信号是微弱的，就需要由测量电路加以放大，以满足显示记录装置的要求。#根据需要测量电路还能进行阻抗匹配、微分、积分、线性化补偿等信号处理工作。#显示记录装置是检测人员和检测系统联系的主要环节，主要作用是使人们了解被测量的大小或变化的过程。#2.传感器的型号有几部分组成，各部分有何
35、意义?#依次为主称（传感器） 被测量转换原理序号#主称传感器，代号C；#被测量用一个或两个汉语拼音的第一个大写字母标记。#见附录表2；#转换原理用一个或两个汉语拼音的第一个大写字母标记。#见附录表3；#序号用一个阿拉伯数字标记，厂家自定，用来表征产品设计特性、性能参数、产品系列等。#若产品性能参数不变，仅在局部有改动或变动时，其序号可在原序号后面顺序地加注大写字母A、B、C等，（其中I、Q不用）。#例：#应变式位移传感器：# C WY-YB-20；#光纤压力传感器：#C Y-GQ-2。#3.测量稳压电源输出电压随负载变化的情况时，应当采用何种测量方法?# 如何进行?#答：#测定稳压电源输出电压
36、随负载电阻变化的情况时，最好采用微差式测量。#此时输出电压认可表示为U0，U0=U+U，其中U是负载电阻变化所引起的输出电压变化量，相对U来讲为一小量。#如果采用偏差法测量，仪表必须有较大量程以满足U0的要求，因此对U，这个小量造成的U0的变化就很难测准。#测量原理如下图所示：#图中使用了高灵敏度电压表毫伏表和电位差计，Rr和E分别表示稳压电源的内阻和电动势，凡表示稳压电源的负载，E1、R1和Rw表示电位差计的参数。#在测量前调整R1使电位差计工作电流I1为标准值。#然后，使稳压电源负载电阻R1为额定值。#调整RP的活动触点，使毫伏表指示为零，这相当于事先用零位式测量出额定输出电压U。#正式测
37、量开始后，只需增加或减小负载电阻RL的值，负载变动所引起的稳压电源输出电压U0的微小波动值U，即可由毫伏表指示出来。#根据U0=U+U，稳压电源输出电压在各种负载下的值都可以准确地测量出来。#微差式测量法的优点是反应速度快，测量精度高，特别适合于在线控制参数的测量。# 用微差式测量方法测量稳压电源输出电压随负载的变化#4.某线性位移测量仪，当被测位移由4.5mm变到5.0mm时，位移测量仪的输出电压由3.5V减至2.5V，求该仪器的灵敏度。#解：#该仪器的灵敏度为#mV/mm#5.某测温系统由以下四个环节组成，各自的灵敏度如下：# 铂电阻温度传感器：# 0.45/# 电桥：# 0.02V/#
38、放大器：# 100（放大倍数）# 笔式记录仪：# 0.2cm/V#求：#（1）测温系统的总灵敏度；# （2）记录仪笔尖位移4cm时，所对应的温度变化值。# #解：#（1）测温系统的总灵敏度为# cm/#（2）记录仪笔尖位移4cm时，所对应的温度变化值为#6.有三台测温仪表，量程均为0800，精度等级分别为2.5级、2.0级和1.5级，现要测量500的温度，要求相对误差不超过2.5，选那台仪表合理?#解：#2.5级时的最大绝对误差值为20，测量500时的相对误差为4；#2.0级时的最大绝对误差值为16，测量500时的相对误差为3.2；#1.5级时的最大绝对误差值为12，测量500时的相对误差为2
39、.4。#因此，应该选用1.5级的测温仪器。#7.什么是系统误差和随机误差?#正确度和精密度的含义是什么?# 它们各反映何种误差?#答：#系统误差是指在相同的条件下，多次重复测量同一量时，误差的大小和符号保持不变，或按照一定的规律变化的误差。#随机误差则是指在相同条件下，多次测量同一量时，其误差的大小和符号以不可预见的方式变化的误差。#正确度是指测量结果与理论真值的一致程度，它反映了系统误差的大小，精密度是指测量结果的分散程度，它反映了随机误差的大小。#8.服从正态分布规律的随机误差有哪些特性?# #答：#服从正态分布规律的随机误差的特性有：#对称性 随机误差可正可负，但绝对值相等的正、负误差出
40、现的机会相等。#也就是说f（）- 曲线对称于纵轴。#有界性 在一定测量条件下，随机误差的绝对值不会超过一定的范围，即绝对值很大的随机误差几乎不出现。#抵偿性 在相同条件下，当测量次数n时，全体随机误差的代数和等于零，即#。#单峰性 绝对值小的随机误差比绝对值大的随机误差出现的机会多，即前者比后者的概率密度大，在=0处随机误差概率密度有最大值。# #9.等精度测量某电阻10次，得到的测量列如下：# R1167.95 R2167.45 R3167.60 R4167.60 R5167.87 R6167.88 R7168.00 R8167.850 R9167.82 R10167.61#（1）求10次测
41、量的算术平均值#，测量的标准误差和算术平均值的标准误差s。#（2）若置信概率取99.7，写出被测电阻的真值和极限值。#解：#（1）求10次测量的算术平均值#，测量的标准误差和算术平均值的标准误差s。#（2）若置信概率取99.7，被测电阻的真值为：#极限值为：#10.试分析电压输出型直流电桥的输入与输出关系。#答：#如图所示，电桥各臂的电阻分别为R1、 R2、R3、R4。#U为电桥的直流电源电压。#当四臂电阻R1=R2=R3=R4=R时，称为等臂电桥；#当R1=R2=R,R3=R4=R（RR）时，称为输出对称电桥；#当R1=R4=R，R2=R3 =R（RR）时，称为电源对称电桥。#直流电桥电路
42、#当电桥输出端接有放大器时，由于放大器的输入阻抗很高，所以可以认为电桥的负载电阻为无穷大，这时电桥以电压的形式输出。#输出电压即为电桥输出端的开路电压，其表达式为# （1）#设电桥为单臂工作状态，即R1为应变片，其余桥臂均为固定电阻。#当R1感受被测量产生电阻增量R1时，由初始平衡条件R1R3=R2R4得#，代入式（1），则电桥由于R1产生不平衡引起的输出电压为 # （2）#对于输出对称电桥，此时R1=R2=R,R3=R4=R，当R1臂的电阻产生变化R1=R，根据（2）可得到输出电压为# （3）#对于电源对称电桥，R1=R4=R,R2=R3=R。#当R1臂产生电阻增量R1=R时，由式（2）得
43、# （4）#对于等臂电桥R1=R2=R3=R4=R，当R1的电阻增量R1=R时，由式（2）可得输出电压为# （5）#由上面三种结果可以看出，当桥臂应变片的电阻发生变化时，电桥的输出电压也随着变化。#当R#R时，电桥的输出电压与应变成线性关系。#还可以看出在桥臂电阻产生相同变化的情况下，等臂电桥以及输出对称电桥的输出电压要比电源对称电桥的输出电压大，即它们的灵敏度要高。#因此在使用中多采用等臂电桥或输出对称电桥。#在实际使用中为了进一步提高灵敏度，常采用等臂电桥，四个被测信号接成两个差动对称的全桥工作形式，R1=R+R,R2=R-R,R3=R+R,R4=R-R，将上述条件代入式（1）得# （6）
44、#由式（6）看出，由于充分利用了双差动作用，它的输出电压为单臂工作时的4倍，所以大大提高了测量的灵敏度。#第2章 电阻式传感器思考题答案#1.金属电阻应变片与半导体材料的电阻应变效应有什么不同?#答：#金属电阻的应变效应主要是由于其几何形状的变化而产生的，半导体材料的应变效应则主要取决于材料的电阻率随应变所引起的变化产生的。#2.直流测量电桥和交流测量电桥有什么区别?#答：#它们的区别主要是直流电桥用直流电源，只适用于直流元件，交流电桥用交流电源，适用于所有电路元件。#3.热电阻测量时采用何种测量电路?#为什么要采用这种测量电路?#说明这种电路的工作原理。#答：#通常采用电桥电路作为测量电路。
45、#为了克服环境温度的影响常采用下图所示的三导线四分之一电桥电路。#由于采用这种电路，热电阻的两根引线的电阻值被分配在两个相邻的桥臂中，如果#，则由于环境温度变化引起的引线电阻值变化造成的误差被相互抵消。#热电阻的测量电路#4.采用阻值为120灵敏度系数K=2.0的金属电阻应变片和阻值为120的固定电阻组成电桥，供桥电压为4V，并假定负载电阻无穷大。#当应变片上的应变分别为1和1 000时，试求单臂、双臂和全桥工作时的输出电压，并比较三种情况下的灵敏度。#解：#单臂时#，所以应变为1时#/V，应变为1000时应为#/V；#双臂时#，所以应变为1时#/V，应变为1000时应为#/V；#全桥时#，所
46、以应变为1时#/V，应变为1000时应为#/V。#从上面的计算可知：#单臂时灵敏度最低，双臂时为其两倍，全桥时最高，为单臂的四倍。#5.采用阻值R=120灵敏度系数K=2.0的金属电阻应变片与阻值R=120的固定电阻组成电桥，供桥电压为10V。#当应变片应变为1000时，若要使输出电压大于10mV，则可采用何种工作方式（设输出阻抗为无穷大）？#解：#由于不知是何种工作方式，可设为n，故可得：#mV#得n要小于2，故应采用全桥工作方式。#6.如图所示为一直流电桥，供电电源电动势E=3V，R3=R4=100，R1和R2为同型号的电阻应变片，其电阻均为50，灵敏度系数K=2.0。#两只应变片分别粘贴
47、于等强度梁同一截面的正反两面。#设等强度梁在受力后产生的应变为5 000，试求此时电桥输出端电压U0。#题6图#解：#此电桥为输出对称电桥，故#/mV#7.光敏电阻有哪些重要特性，在工业应用中是如何发挥这些特性的？#答：#光敏电阻是采用半导体材料制作，利用内光电效应工作的光电元件。#它的重要特性是在无光照时阻值非常大，相当于断路，有光照时阻值变得很小，相当于通路。#在工业应用中主要就是通过光的变化来各种电路的控制。#第3章 电容式传感器思考题答案#1.试分析变面积式电容传感器和变间隙式电容的灵敏度?#为了提高传感器的灵敏度可采取什么措施并应注意什么问题?#答：#如图所示是一直线位移型电容式传感
48、器的示意图。#当动极板移动x后，覆盖面积就发生变化，电容量也随之改变，其值为#C=b（a-x）/d=C0-b#x/d （1）#电容因位移而产生的变化量为#其灵敏度为 #可见增加b或减小d均可提高传感器的灵敏度。#直线位移型电容式传感器#2.为什么说变间隙型电容传感器特性是非线性的?#采取什么措施可改善其非线性特征?#答：#下图为变间隙式电容传感器的原理图。#图中1为固定极板，2为与被测对象相连的活动极板。#当活动极板因被测参数的改变而引起移动时，两极板间的距离d发生变化，从而改变了两极板之间的电容量C。#设极板面积为A，其静态电容量为#，当活动极板移动x后，其电容量为# （1）#当x#d时 #
49、 则# （2）#由式（1）可以看出电容量C与x不是线性关系，只有当 x# t0）。#在导体内部，热端的自由电子具有较大的动能，向冷端移动，从而使热端失去电子带正电荷，冷端得到电子带负电荷。#这样，导体两端便产生了一个由热端指向冷端的静电场。#该电场阻止电子从热端继续跑到冷端并使电子反方向移动，最后也达到了动态平衡状态。#这样，导体两端便产生了电位差，我们将该电位差称为温差电动势。#3简述热电偶的几个重要定律，并分别说明它们的实用价值。#答：#一是匀质导体定律：#如果热电偶回路中的两个热电极材料相同，无论两接点的温度如何，热电动势为零。#根据这个定律，可以检验两个热电极材料成分是否相同，也可以检
50、查热电极材料的均匀性。#二是中间导体定律：#在热电偶回路中接入第三种导体，只要第三种导体的两接点温度相同，则回路中总的热电动势不变。#它使我们可以方便地在回路中直接接入各种类型的显示仪表或调节器，也可以将热电偶的两端不焊接而直接插入液态金属中或直接焊在金属表面进行温度测量。#三是标准电极定律：#如果两种导体分别与第三种导体组成的热电偶所产生的热电动势已知，则由这两种导体组成的热电偶所产生的热电动势也就已知。#只要测得各种金属与纯铂组成的热电偶的热电动势，则各种金属之间相互组合而成的热电偶的热电动势可直接计算出来。#四是中间温度定律：#热电偶在两接点温度t、t0时的热电动势等于该热电偶在接点温度
51、为t、tn和tn、t0时的相应热电动势的代数和。#中间温度定律为补偿导线的使用提供了理论依据。#4试述热电偶冷端温度补偿的几种主要方法和补偿原理。#答：#热电偶冷端温度补偿的方法主要有：#一是冷端恒温法。#这种方法将热电偶的冷端放在恒温场合，有0恒温器和其他恒温器两种；#二是补偿导线法。#将热电偶的冷端延伸到温度恒定的场所（如仪表室），其实质是相当于将热电极延长。#根据中间温度定律，只要热电偶和补偿导线的二个接点温度一致，是不会影响热电动势输出的；#三是计算修正法。#修正公式为：#；#四是电桥补偿法。#利用不平衡电桥产生的电动势补偿热电偶因冷端波动引起的热电动势的变化，工作原理如下图所示。#图
52、中，e为热电偶产生的热电动势，U为回路的输出电压。#回路中串接了一个补偿电桥。#R1R5及RCM均为桥臂电阻。#RCM是用漆包铜丝绕制成的，它和热电偶的冷端感受同一温度。#R1R5均用锰铜丝绕成，阻值稳定。#在桥路设计时，使R1=R2，并且R1、R2的阻值要比桥路中其他电阻大得多。#这样，即使电桥中其他电阻的阻值发生变化，左右两桥臂中的电流却差不多保持不变，从而认为其具有恒流特性。#线路设计使得I1=I2=I/2=0.5mA。#回路输出电压U为热电偶的热电动势e、桥臂电阻RCM的压降URCM及另一桥臂电阻R5的压降UR5三者的代数和：#当热电偶的热端温度一定，冷端温度升高时，热电动势将会减小。
53、#与此同时，铜电阻RCM的阻值将增大，从而使URCM增大，由此达到了补偿的目的。#自动补偿的条件应为# # #5用镍铬-镍硅（K）热电偶测量温度，已知冷端温度为40，用高精度毫伏表测得这时的热电动势为29.188mV，求被测点的温度。#解：#由镍铬-镍硅热电偶分度表查出E（40，0）=1.638mV，根据式（5-2-1）计算出#再通过分度表查出其对应的实际温度为#6已知铂铑10-铂（S）热电偶的冷端温度t025，现测得热电动势E（t，t0）11.712mV，求热端温度是多少度?#解：#由铂铑10-铂热电偶分度表查出E（25，0）=0.161mV，根据式（5-2-1）计算出#再通过分度表查出其对
54、应的实际温度为#7已知镍铬-镍硅（K）热电偶的热端温度t800，冷端温度t025，求E（t，to）是多少毫伏?#解：#由镍铬-镍硅热电偶分度表可查得E（800，0）=33.275mV，E（25，0）=1.024 mV，故可得# E（800，5）=33.275-1.024=32.251mV#8现用一支镍铬-康铜（E）热电偶测温。#其冷端温度为30，动圈显示仪表（机械零位在0）指示值为400，则认为热端实际温度为430，对不对?#为什么?#正确值是多少?#解：#不对，因为仪表的机械零位在0，正确值为400。#9如图5.14所示之测温回路，热电偶的分度号为K，毫伏表的示值应为多少度?#答：#毫伏表的
55、示值应为（t1-t2-60）。#10用镍铬-镍硅（K）热电偶测量某炉温的测量系统如图5.15所示，已知：#冷端温度固定在0，t030，仪表指示温度为210，后来发现由于工作上的疏忽把补偿导线#，相互接错了，问：#炉温的实际温度t为多少度?#解：#实际温度应为270，因为接反后不但没有补偿到，还抵消了30，故应该加上60。#图5.14 图5.15#第6章 压电传感器习题答案#1为什么说压电式传感器只适用于动态测量而不能用于静态测量?#答：#因为压电式传感器是将被子测量转换成压电晶体的电荷量，可等效成一定的电容，如被测量为静态时，很难将电荷转换成一定的电压信号输出，故只能用于动态测量。#2压电式传
56、感器测量电路的作用是什么?#其核心是解决什么问题?#答：#压电式传感器测量电路的作用是将压电晶体产生的电荷转换为电压信号输出，其核心是要解决微弱信号的转换与放大，得到足够强的输出信号。# #3一压电式传感器的灵敏度K110pCMPa，连接灵敏度K2=0.008VpC的电荷放大器，所用的笔式记录仪的灵敏度K3=25mmV，当压力变化p=8MPa时，记录笔在记录纸上的偏移为多少?#解：#记录笔在记录纸上的偏移为# S=10#0.008#25#8=16/mm#4某加速度计的校准振动台，它能作50Hz和1g的振动，今有压电式加速度计出厂时标出灵敏度K100mVg，由于测试要求需加长导线，因此要重新标定
57、加速度计灵敏度，假定所用的阻抗变换器放大倍数为1，电压放大器放大倍数为100，标定时晶体管毫伏表上指示为9.13V，试画出标定系统的框图，并计算加速度计的电压灵敏度。#解：#此加速度计的灵敏度为# # mV/g#标定系统框图如下：#第7章 光电式传感器#1光电效应有哪几种?#与之对应的光电元件各有哪些?#答：#光电效应有外光电效应、内光电效应和光生伏特效应三种。#基于外光电效应的光电元件有光电管、光电倍增管等；#基于内光电效应的光电元件有光敏电阻、光敏晶体管等；#基于光生伏特效应的光电元件有光电池等。#2常用的半导体光电元件有哪些?#它们的电路符号如何?#答：#常用的半导体光电元件有光敏二极管、光敏三极管和光电池三种。#它们的电路符号如下图所示：#3对每种半导体光电元件，画出一种测量电路。#答：#光敏二极管、三;i:2;s:54:完整版填色画托马斯小火车宝宝涂色画#;
