山东大学本科电子技术模拟题带答案1

电子技术模拟题 2017年

一、单项选择题：在下列各题中，将正确的答案代码填入括号内

1． P 型半导体中空穴数量远比电子多得多，因此该半导体

应（）。

(a) 带正电

(b) 带负电 (c) 不带电

2．电路如图所示, 所有二极管均为理想元件，则 D 1、D 2、D 3的工作状态为（）。

(a) D 1导通，D 2、D 3 截止 (b) D 1、D 2截止， D 3 导通 (c) D 1、D 3截止， D 2导通 (d) D 1、D 2、D 3均截止

3．电路如图所示，二极管 D 为理想元件，输入信号 u i 为如图所示的三角波，则输出电压 u O 的

最大值为（）。

(a) 5 V (b) 10 V (c) 2 V (d) 7 V

u O

4．晶体管处于截止状态时，集电结和发射结的偏置情况为（）。

(a) 发射结反偏，集电结正偏 (b) 发射结、集电结均反偏 (c) 发射结、集电结均正偏 (d) 发射结正偏，集

电结反偏

5．某固定偏置单管放大电路的静态工作点Q 如图所示，欲使工作点移至Q ′需使( )。

(a ) 偏置电阻R B 增大。 (b ) 集电极电阻R C 减小 (c ) 偏置电阻R B 减小

CE (V)

=40μ

6．采用差动放大电路是为了( )。

(A) 稳定电压放大倍数 (B)增强带负载能力 (C) 提高输入阻抗（D ）克服零点漂移

7．电路如图所示，运算放大器的饱和电压为±12V ，设稳压管的稳定电压为6V ，正向压降为零，当输入电压u i =1V 时，则输出电压u O 等于( )。

(a) 12V (b) 6V (c)0V

u i

8．自激正弦振荡器是用来产生一定频率和幅度的正弦信号的装置，此装置之所以能输出信号是因为（）。

(a) 有外加输入信号 (b) 满足了自激振荡条件

9．一个振荡器要能够产生正弦波振荡，电路的组成必须包含（ )。

(a) 放大电路，负反馈电路 (b) 负反馈电路、选频电路

10 .逻辑电路如图所示，A=“0”，B=“1” 时，C 脉冲来到后 JK 触发器（）。

(a) 具有计数功能 (b) 置“0” (c) 置“1” (d) 保持原状态

11 .分析某时序逻辑电路的状态表，判定它是（）。

(a) 移位寄存器

(b) 二进制计数器 (c) 十进制计数器

12.已知某半导体存储器的容量为1024×4，则其具有的地址线数应为（）。

(a) 4 (b) 8 (c) 10 (d) 2 13. T 形电阻网络 D/A 转换器是由（）组成。

(a) T 形电阻网络和集成运算放大器 (b) T 形电阻网络和触发器 (c) T 形电阻网络和振荡器

二、计算题

放大电路如图所示，晶体管的电流放大系数 β=50，

U BE .V =06 ，R B1=110 k Ω， R B2= 10 k Ω， R C = 6 k Ω，R E = 400 Ω，

R L ＝ 6 k Ω，要求：(1) 计算静态工作点；(2) 画出微变等效电路；(3) 计算电

压放大倍数。

u o 12V

三、分析表达题

电路如图所示，R R R 2

45k

===10Ω，R 1k =1Ω ，求：

(1) R 3 ，R 6 的阻值。

(2) A u u U F O I ==/?

(3) 若运算放大器的电源电压为±15V ，

输入电压 u 1V =2，则输出电压

u O =?

u O

四、分析计算题

整流滤波电路如图所示，二极管是理想元件，电容

C F =500μ，负载电阻R L k =5Ω ，开关 S 1闭合、S 2 断开时，直流

电压表

()V 的读数为1414.V ，求：

(1) 开关 S 1 闭合、S 2 断开时，直流电流表 ()A 的读数 ; (2) 开关 S 1 断开、S 2 闭合时，直流电流表 ()A 的读数 ;

(3) 开关 S 1、S 2 均闭合时，直流电流表()A 的读数。 (设电流表内阻为零，电压表内阻为无穷大 )。

u 1

五、分析逻辑电路

逻辑电路如图所示，写出逻辑式，化简之，并列出状态表。

A C

电子技术参考答案

三、 (1) R R R 312//k =≈1Ω，R R R 645//k ==5Ω (2) A u u U F O I ==/20

(3) 当u I V =2，则u O 约等于 30V

要点 A u u u u u U F

O I O2O1I

==- u R

R u u O I I 12110

=-=- u R

R u u O O1I 25410

=-= 故 A u u U F

I I

==2020 四、(1) 开关 S 1闭合、S 2 断开时 : ()A 的读数为零。

(2) 开关 S 1 断开、S 2闭合时，U 214142

100=

V V; U U O V V ==?=0909100

902..; ()A 的读数为 U R O L mA mA =

=90

18， (3)开关 S 1、S 2 均闭合时，U U O V V ==?=12

121001202..; ()A 的读数为

U R O L mA mA ==1205

24。五、

F ABC A ABC B ABC C =++

=++()()ABC A B C =+++ABC A B C ()

ABC

大学英语四级模拟试题四(附含答案解析)

大学英语四级模拟题四 Part One Reading Comprehension (2’×10 = 20’) Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A), B), C) and D). You should decide on the best choice and mark the corresponding letter on the Answer Sheet with a single line through the centre. Passage One Air pollution can spread from city to city. It even spreads from one country to another. Some northern European countries have had “black snow”from pollutants that have traveled through the air from other countries and have fallen with the snow. So air pollution is really a global problem. Air pollution can kill babies, older people, and those who have respiratory（呼吸的）diseases. As found in cities, air pollution increases the risks of certain lung diseases. Air pollution can cause both airplane and car accidents because it cuts down visibility （能见度）. There are other possible health dangers from air pollution that we don’t know much about. For example, scientists are trying to find out whether chemicals that reach us from the air may cause changes in our cells. These changes might cause babies to be born with serious birth defects. Scientists are trying to learn how all the many chemicals are apt（易于的）to take into our bodies from air, water, food, and even medicines act together to affect our health and the way our bodies work. That is another reason why it is so important to begin to control pollution now instead of waiting until we learn all the answers. Air pollution costs us a lot of money. It corrodes（腐蚀）our buildings. It damages farm crops and forests. It has a destructive effect on our works of art. The cost of all this damage to our government is great. It would be much more worthwhile, both for us and for the government, to spend our tax dollars on air pollution control. 1. Air pollution may lead to airplane accidents because . A. it may cause pilots to be ill B. engines may fail from the air-borne dirt C. visibility is reduced D. it brings a lot of black snow 2. Scientists are trying to find a link between pollution and . A. intelligence levels B. birth problems C. man’s behavior D. the nervous system 3. Scientists have not yet determined . A. all of the effects of pollution on the human body B. how pollution can be controlled successfully C. when the atmosphere first became polluted D. how some snow becomes black 4. The author suggests that before air pollution becomes more serious, . A. factories will be forced to stop operating B. buildings should be protected C. the earth will begin to grow colder D. more money should be spent to solve the problem 5. We can conclude that . A. civilization may be ruined if pollution is not controlled B. pollution is more serious in Europe than it is in America C. most people do not know that pollution is a serious problem D. we should learn all the answers before we begin to control pollution Passage Two Stiletto heels could be banned from the workplace because of health and safety reasons, according to British Trade Union bosses. The Trade Union Congress, predominantly male, has proposed a motion arguing that high heels are disrespectful to women while they also contribute to long term injuries. They propose instead that women wear “sensible shoes”with an inch heel limit in an attempt to avoid future foot and back pain as well as injuries. The motion is due to be debated at next month’s conference. The motion states: “Congress believes high heels may look glamorous on the Hollywood catwalks but are completely in appropriate for the day-to-day working environment. Feet bear the burden of daily life, and for many workers prolonged standing, badly fitted footwear, and in particular high heels can be a hazard. Around two million days a year are lost through sickness as a result of lower limb disorders. Wearing high heels can cause long-term foot problems and also serious foot, knee and back pain and damaged joints. Many employers in the retail sector force women workers to wear high heels as part of their dress code. More must be done to raise awareness of this problem so that women workers and their feet are protected.” Nadline Dorries, the Tory Member of Parliament, however criticized the motion and said the extra height heels give women can help them when in the workplace. “I’m 5ft 3in and need every inch of my Christian Louboutin heels to look my male colleagues in the eye,”she said. “If high heels were banned in Westminster, no one would be able to find me. The Trade Union leaders need to get real, stop using obvious sexist tactics by discussing women’s

电子技术基础试卷1

电子上期期末考试试卷考号姓名一、填空题（30空×1分=30分） 1、在N型半导体中是多子，在P型半导体中是少子。 2、PN结加正向电压时，加反向电压时，这种特性称为PN结的特性。 3、三极管的极限参数有：____________、____________和____________。 4、加在二极管两端的反向电压超过U(BR)时，二极管将被。流过二极管的正向电流长时间超过I FM时，二极管将被。 5、三极管的发射极电流、集电极电流和基极电流关系为。 6、NPN三极管三个电极的电位关系是。 7、三极管输出特性曲线可以分为区、区和________________区。 8、放大器的放大倍数有____________、__________和____________。 9、放大器必须设置，能避免产生非线性失真。 10、二极管特性：________________性，它的符号________。 11、三极管有________、________、________三个电极，________和 ________两个PN结。 12、基本共发射放大电路又称为____________，其缺点是____________，它的输出电压与输入电压相位____ ______，因此这种放大电路又称为____________。二、选择（将正确的答案填入对应的表格中10×2分=20分） 1、在N型半导体中（）。 A、只有自由电子 B、只有空穴 C、有空穴也有自由电子 2、下列说法错误的是（）。 A、I E =I B +I C适合各类三极管 B、I C =βI B适合各类三极管 C所有三极管放大都要满足发射结正偏，集电结反偏

大学英语一模拟题及答案

《大学英语1》模拟考试试卷 1.He realized that his( attitude ) on these matters was wrong. 2.You should take ( advantage ) of this chance and try to make a good impression on them. 3.It seems that they had little in (common) even though they are twin brother. spend know how to (improve) your to without having grades you 4.Do want to more time studying? 5.I don't want to take these shoes mainly because they are too(fancy) for me. achievement high help get (score)on regularly 6.Going over your notes can tests. asleep. fell (comfortable)armchair,my 7.While sitting in the grandfather 8.Words can't (describe) the beauty of the scene. may 9.Nowadays many children pleasant (surroundings) ,which live in the cause some problems. 10.He left school for (economic) reasons. 分，共（每小题择法二、语选题210分）There are five questions and four choices marked A,B,C and D for each question,choose the best answer. 1.There are more __D__ in Bristol than in any other city I know. A. football team B. footballs team 5 / 1 C. footballs teams D. football teams 2.This is the ___B____ leaning tower in Pisa. A. 180-feet-high B. 180-foot-high C. 180-foot high D. 180 foot high

模拟电子技术考试试卷1

《模拟电子技术》考试试卷1 一、填空题（20分，每题2分） 1、半导体三极管按极性可分为_____型和_____型二类。 2、半波整流电路中，二极管承受的最大反向电压U RM =_______U 2，负载电压U O =_________U 2。 3、如果温度升高三极管的输出特性曲线将向________移动。 4、抑制零点飘移的电路称为___________________________.。 5、乙类互补对称功率放大电路将产生__________失真，而________互补对称功率放大电路，可以消除这种失真。 6、C Ｗ79XX 系列三端稳压器各脚功能是：①脚________； ②脚________；③脚________。 7、当信号发生器电压调在1V ，现在用40dB 衰减其输出电压为______mV 。 8、当示波器幅度旋钮位置V/div 在0.5V 时读数为4格，其电压的有效值为______V 。 9、当示波器频率旋钮位置T/div 在0.5ms 时读数为2格，其周期为______Hz 。 10、要抑制50Hz 的工频信号的影响，应选择________ 滤波电路。二、判断题（20分，每题2分，对的打√错的打╳） 1、稳压二极管必需工作在正向导通状态。（） 2、在集成电路中采用直接耦合。（） 3、石英晶体振荡电路的优点是其振荡频率的稳定性很高。（） 4、尽管开关稳压电源的体积小、稳压范围宽但它的功率消耗很大。（） 5、在正弦波振荡电路中只能引入正反馈，不允许出现负反馈。（） 6、射极跟随器的放大倍数为1因此在电路不起任何作用。（） 7、在多级放大电路中前级放大的工作点宜设置在较低位置。（） 8、硅稳压管稳压电路只适用于负载小的场合且输出电压不能调节。（） 9、跟据集成运算放大器电路虚断原则得到i +=i - 。（） 10、判断正负反馈时，我们采用瞬时极性法，（）当使净输入信号增强时即为负反馈。三、简答题（25分，每题5分） 1、电路如下图所示，二极管是导通还是截止，R=10K ，试求出AO 两点间的电压U AO ？（设二极管的正向压降是0.7V ） A O 8V D 2、如下图所示，稳压管D 1、D 2的稳定电压分别为8V 、6V ，设稳压管的正向压降是0.7V ，试求U O 。

北语大学英语(二)模拟试卷和答案

《大学英语（二）》模拟试卷一注意： 1．试卷保密，考生不得将试卷带出考场或撕页，否则成绩作废。请监考老师负责监督。 2．请各位考生注意考试纪律，考试作弊全部成绩以零计算。 3．本试卷满分100分，答题时间为90分钟。 4.本试卷分为试题卷和答题卷，所有答案必须答在答题卷上，答在试题卷上不给分。 I.Multiple Choice. (2 points for each, altogether 40 points) Directions:There are 20 sentences in this section. Beneath each sentence there are four choices respectively marked by letters A, B, C and D. Choose the word that you think best complete the sentence. Write your answers on the answer sheet. 1. Studies have shown _______ teenagers often suffer from depression. [A] that[B] which[C] in which[D] in that 2. The party has failed to _______ the majority of voters that it is capable of governing the country. [A] trust[B] credit[C] convince[D] believe 3. Many of us visited the industrial exhibition, __________, to our disappointment, we saw very few high-tech products. [A] where[B] which[C] as[D] that 4. The kids are _______ be hungry when they get home. [A] obliged to[B] bound to[C] desired to[D] motivated to 5. All the characteristics that distinguish birds _______ other animals can be traced to prehistoric times. [A] to[B] between[C] for[D] from 6. Management often works hard to set up a situation work is done in series. [A] that[B] where[C] which[D] what 7. If we _______ everything ready by now, we should be having a terrible time tomorrow.

(精选)山东大学继续教育数字电子技术基础试题3及答案

数字电子技术基础模拟卷 3 一填空。 1 逻辑代数中，基本的运算关系是与、或和非。 2 十进制数27转换成二进制数为11011 ；转换成8421BCD码是00011011 。 3 在逻辑代数中，= +B A A A+ B ；= ⊕1 A。 4 同一个逻辑函数可以有不同的逻辑表达式，但用真值表表示是相同一样的。 5 对于一个4变量的逻辑函数，所构成的最小项的个数是 1 6 ；任意两个最小项相乘等于 0 。 6 两个变量组成的与非关系的逻辑符号是；异或关系的逻辑符号为。 7 集成TTL逻辑门电路的电源电压一般是 5V ；对于不用的输入端如果悬空，其逻辑上相当于高电平1 。 8 集成CMOS逻辑门电路其静态功耗近似为 0 ；对于CMOS与非门，对于多余的输入端应接高电平。二解答下列各题。 1求图示电路的输出F1逻辑函数表达式。 A B F1 1 +V TN1 TN2 TP2 TP1 二大题1小题图 2 求图示电路F2的真值表，并求出最简的“与—或”表达式。

A B C 二大题2小题图三分析下列各题。 1 已知各门电路都是TTL 门电路，试画出输出L 在输入信号作用下的输出波形。 A B C A B C 三大题1小题图 2 设触发器的初始状态为0，试画出输出Q 的波形。三大题2小题图 CP 四一保险柜的锁受三个按键A 、B 、C 控制，要求三个按键同时按下时，或A 、B 两个键同时按下，或A 、C 两个按键同时按下，锁被打开；否则锁闭合。 1 列出上述逻辑问题的真值表。 2 设计采用最少的与非门实现该功能的逻辑电路。 3利用8选1多路数据选择器设计实现上述电路。（8选1数据选择器逻辑符号如图）

大学英语四级模拟试题(1)

洛基英语，中国在线英语教育领导品牌 Model Test 1 Part One Listening Comprehension Section A Directions： In this section, you will hear 10 short conversations. At the end of each conversation, a question will be asked about what was said - Both the conversation and the question will be spoken only once. After each question there will be pause. During the pause, you must read the four choices marked A）, B）, C）and D）, and decide which is the best answer. Then mark the corresponding letter on the Answer Sheet with a line through the centre. Example： You will hear： You will read： A） At the office. B） In the waiting room. C） At the airport. D） In a restaurant. From the conversation we know that the two were talking about some work they had to finish in the evening. This is most likely to have taken place at the office. Therefore, A） At the office is the best answer. You should choose [A] on the Answer Sheet and mark it with a single line through the centre. 1. A） She is not interested in the article. B） She has given the man much trouble. C） She would like to have a copy of the article. D） She doesn't want to take the trouble to read the article. 2. A） He saw the big tower he visited on TV~ B） He has visited the TV tower twice. C） He has visited the TV tower once. D） He will visit the TV tower in June. 3. A） The woman has trouble getting along with the professor. B） The woman regrets having taken up much of the professor's time. C） The woman knows the professor has been busy. D） The woman knows the professor has run into trouble. 4. A） He doesn't enjoy business trips as much as he used to. B） He doesn't think he is capable of doing the job. C） He thinks the pay is too low to support his family, D） He wants to spend more time with his family. 5. A） The man thought the essay was easy. B） They both had a hard time writing the essay. C） The woman thought the essay was easy. D） Neither of them has finished the assignment yet. 6. A） In the park. B） Between two buildings C） In his apartment. D） Under a huge tree. 7. A） It's awfully dull. B） It's really exciting.

电子技术试卷1

电子技术试卷1 一、单项选择题：在下列各题中将唯一正确的答案代码填入括号内 (共30分，每小题2分) 1．在P 型半导体中，多数载流子是（）。 (a) 正离子 (b) 自由电子 (c) 空穴 2. 在图示1-1电路中，二极管的工作状态为（）。 (a) D 1、D 2均导通 (b) D 1导通、D 2截止 (c) D 1截止、D 2导通 3. 某N 沟道场效应晶体管，测得U GS ＝0，漏极电流I D ＝0，则该管的类型为（）。 (a) 耗尽型管 (b) 增强型管 (c) 无法确定 4．放大电路如图1-2所示，V CC ＝12V ，静态时U CE ＝4V ， R C ＝4k Ω，当逐渐加大输入信号u i 时，输出信号u o 首先出现（）。 (a) 截止失真 (b) 饱和失真 (c) 截止和饱和失真 5. 射极输出器的主要特点是（）。 (a) 输入电阻高，输出电阻低，电压放大倍数接近于+1 (b) 输入电阻高，输出电阻高，电压放大倍数接近于－1 (c) 输入电阻低，输出电阻低，电压放大倍数接近于+1 6. 在下列运算放大器的各种应用电路中，运算放大器工作在非线性状态的电路是（）。 (a) 反向比例放大器 (b) 有源滤波器 (c) 电压比较器 7. 已知某个逻辑门电路输入A 、B 和输出F 的波形如图1-3所示，则该逻辑门为（）。 (a) 同或门 (b) 或门 (c) 异或门 8. 逻辑函数表达式ABC BC A C B A F ++= 的最简与或表达式为（）。 (a) BC BC A F += (b) AC C B F += (c) BC AC F += ?1-1 A B F 图1-3 ?1-2

大学英语模拟试题及答案(2020年整理).doc

大学英语模拟题 1、One of my teeth is so ______ that it is going to be missing soon（2）（） A．lose B．loose C．loss D．lost 标准答案：B 2、—How about taking a walk? —Oh, I think it’s ______ cold for a walk （2）（） A．very much B．too much C．much too D．so much 标准答案：C 3、You are supposed to write your composition every ______ line.（2）（） A．one B．a

C．other D．another 标准答案：C 4、After living for years in a big city, they found it difficult to settle ______ in a town.（2）（） A．for B．at C．up D．down 标准答案：D 5、The reason for my absence was ______ I had fallen ill.（2）（） A．why B．because C．for D．that 标准答案：D 6、This is the university ______.（2）（） A．at which do we study B．we are studying

C．we are studying at D．where we study at 标准答案：A 7、It was in this house ______ the important meeting in history was held.（2）（） A．where B．that C．which D．in which 标准答案：B 8、She looked so honest that we all regarded her story ______.（2）（） A．like true B．as true C．like real D．as real 标准答案：B 9、Mrs. Brown as well as her children ______ to go Paris on holiday next

山东大学数字电子技术期末试卷及答案.

试卷A 一、选择题（从每小题的四个备选答案中，选出一个正确答案，并将其号码填在括号内，每小题2分，共20分） 1.将十进制数（18）10转换成八进制数是[ ] ①20 ②22 ③21 ④23 2. 三变量函数 ()BC A C B A F+ = , ,的最小项表示中不含下列哪项[ ] ①m2 ②m5 ③m3 ④m7 3.一片64k×8存储容量的只读存储器（ROM），有[ ] ①64条地址线和8条数据线②64条地址线和16条数据线 ③16条地址线和8条数据线④16条地址线和16条数据线 4.下列关于TTL与非门的输出电阻描述中，正确的是[ ] ①门开态时输出电阻比关态时大②两种状态都是无穷大输出电阻 ③门关态时输出电阻比开态时大④两种状态都没有输出电阻 5.以下各种ADC中，转换速度最慢的是[ ] ①并联比较型②逐次逼进型 ③双积分型④以上各型速度相同 6. 关于PAL器件与或阵列说法正确的是[ ] ①只有与阵列可编程②都是可编程的 ③只有或阵列可编程④都是不可编程的 7. 当三态门输出高阻状态时，输出电阻为[ ] ①无穷大②约100欧姆 ③无穷小④约10欧姆 8.通常DAC中的输出端运算放大器作用是[ ] ①倒相②放大 ③积分④求和 9. 16个触发器构成计数器，该计数器可能的最大计数模值是[ ] ①16 ②32 ③162④216 10.一个64选1的数据选择器有（）个选择控制信号输入端。[ ] ① 6 ②16 ③32 ④64

二、填空题（把正确的内容填在题后的括号内。每空1分，共15分。） 1．已知一个四变量的逻辑函数的标准最小项表示为 ()()13,11,9,8,6,4,3,2,0,,,m d c b a F ∑=，那么用最小项标准表示=* F ，以及=F ，使用最大项标准表示=F ，以及 =F 。 2．具有典型实用意义的可编程逻辑器件包括，，，。 3．为了构成4K ×16bit 的RAM ，需要块1K ×8bit 的RAM ，地址线的高位作为地址译码的输入，地址译码使用的是译码器。 4．在AD 的量化中，最小量化单位为Δ，如果使用四舍五入法，最大量化误差为 Δ，如果使用舍去小数法，最大量化误差为 Δ。 5．如果用J-K 触发器来实现T 触发器功能，则T,J,K 三者关系为；如果要用J-K 触发器来实现D 触发器功能，则D,J,K 三者关系为。三、简答题（每小题5分，共10分） 1．用基本公式和定理证明下列等式： ()ABC BC A C AB B C AB ++=+ 2．给出J-K 触发器的特征方程，状态转移真值表，状态转移图。四、分析题（25分） 1．8选1数据选择器CC4512的逻辑功能如表4.1所示。试写出图4.1所示电路输出端 F 的最简与或形式的表达式。（9分）表4.1 CC4512功能表 2. 如图4.2电路由CMOS 传输门构成。试写出输出端的逻辑表达式。（8分）

大学英语四级模拟试题(4)

洛基英语，中国在线英语教育领导品牌 LISTENING COMPREHENSION 1. A） He must read a lot of books. B） He doesn't like history. C） He can't get the books he needs. D） He has lost his watch. 2. A） Mild. B） Warm. C） Hot. D） Cold. 3. A） The light couldn't be turned off. B） The hot water was running. C）There was no hot water. D） There was no heat. 4. A） Tom was unable to hear well. B） Tom didn't say anything at the meeting. C） Tom didn't listen to him. D） Tom went out before the meeting was over. 5. A） In a restaurant. B） At a post office. C） In a hotel. D） At the railway station. 6. A） She couldn't find where the courses were offered. B） She has already taken one. C） The courses are not well organized. D） Not all the courses are bad. 7. A）？？ 15. B）？？ 150. C）？？ 60. D）？？ 30. 8. A） 8：30. B） 7：30. C） 8：00. D） 9：00. 9. A） Finish the novel. B） Return the novel. C） Lend the novel D） Read the novel. 10. A） He is a secretary. B） He is a newspaperman. C） He is a novelist. D） He is a businessman. Passage 1Questions 11 to 13 are based on the passage you have just heard. 11. A） He wasn't satisfied with its size. B） He wasn't satisfied with its power. C） There were no units for measuring power. D） There were few people who liked this engine. 12. A） Lifting a 3,300-pound weight 10 feet into the air in one hour. B）Work a horse could do in one hour. C） Lifting a 3,300-pound weight 10 feet into the air in 10 minutes. D） Work a horse could do in one minute. 13. A） Watt's Engine B） The Beginning of Horsepower C） Units of Measure D） How to Measure an Engine Passage 2Questions 14 to 16 are based on the passage you have just heard. 14. A） He doesn't think flying is fun. B） He feels he is a bus driver. C）He is responsible for the plane and the passengers. D） He is governed by instruments and regulations. 15. A） He enjoyed more freedom. B） Flying was entirely different then. C）He had no responsibility at all. D） He relied on his experience only. 16. A） By looking at the roof of every house. B） By calling a station for information. C） By landing immediately. D） By following a railway line. Passage 3Questions 17 to 20 are based on the passage you have just heard. 17. A） Because she did not speak, except when it was necessary. B） Because she could always find people who were able to help her. C） Because she had a guide who could speak English well. D） Because she had always had a pencil and some paper with her.

数字电子技术基础试题及答案(1)

5.某地址译码电路如图2所示，当输入地址变量 A7-A0的状态分别为什么状态时，丫1、丫6分别才为低电平(被译中) 数字电子技术基础期末考试试卷一、填空题 1. 时序逻辑电路一般由 ________________ 和 _______________ 两分组成。 2. 十进制数(56) 10转换为二进制数为 ____________ 和十六进制数为 __________ 3. 串行进位加法器的缺点是 _________ ，想速度高时应采用 ____________ 加法器＜ 4. 多谐振荡器是一种波形 _________ 电路，它没有稳态，只有两个 ______________ 5. 用6个D 触发器设计一个计数器，则该计数器的最大模值M ________________ 二、化简、证明、分析综合题: 1. 写出函数F (A,B,C,D) = A B C D E 的反函数 2. 证明逻辑函数式相等： BC D D(B C)(AD B) B D 3. 已知逻辑函数 F= E( 3,5,8,9 , 10, 12) +E d(0,1,2) (1) 化简该函数为最简与或式： (2) 画出用两级与非门实现的最简与或式电路图： 4. 555定时器构成的多谐振动器图1所示，已知R 1=1K Q , R 2=8.2K Q , C=0.1卩F 试求脉冲宽度T ,振荡频率f 和占空比q 。 ) 级班 ( 业专 M As As 扣 As

6?触发器电路就输入信号的波形如图 3 所示，试分别写出D 触发器的Q 和Q1 的表达式，并画出其波形。 Q n+1= 7.已知电路如图4所示，试写出： ① 驱动方程； ② 状态方程； ③ 输出方程； ④ 状态表； ⑤ 电路功能。二、设计题：(每10分，共20分) 1 ?设计一个三变量偶检验逻辑电路。当三变量 A B C 输入组合中的“ T 的个数为偶数时F=1，否则F=0。选用8选1数选器或门电路实现该逻辑电路。要求: (1)列出该电路F(A,B,C)的真值表和表达式; (2)画出逻辑电路图 2 .试用74161、3-8译码器和少量门电路，实现图 5所示波形V01 VO2 其中CP 为输入波形。要求： 1 A Rd O E 營 _TLnJTTLTL D= J - Q i =

大学英语网考试题及答案doc资料

大学英语网考试题及答案大学英语B统考模拟试卷及参考答案一第一部分交际英语 1.— Would you mind helping me to get it upstairs? — _____ A. Yes, it is. B. No, it isn't. C. Sure. D. No, of course not. 正确答案：D 题目解析：译文：你能帮我把它拿到楼上去吗？解析：A是的，它是。B不，它不是。C当然。D不，当然不介意。所以根据题意正确答案为D 2.— Is this beautiful? — _____ A. Yes, rarely have I seen this before. B. Yes, I need a rest. C. No, tomorrow will be fine. D. No, the work should be done by him. 正确答案：A 题目解析：译文：这个好看吗？解析：A是的，我之前很少看到过这么好看的。 B是的，我需要休息。C不，明天就可以。D不，这项工作需要由他来完成。根据题意正确答案为A。 3.― _____ ― An accident has happened. A. Where was the accident? B. What happened? C. When was the accident? D. Why did it happen? 正确答案：B 题目解析：译文：一场事故发生了。解析：答案A这场事故在哪儿？答案B发生什么事情了啊？答案C这个事故什么时候发生的啊。答案D为什么会发生啊？根据回答表示问的是发生什么了，正确答案选B。 4.― Excuse me, how soon does this train leave? ― _____ A. It leaves every half an hour. B. It leaves in ten minutes. C. The next trains leaves at ten. D. There is one at four. 正确答案：B