【单选题】
电路的作用是实现能量的传输和转换、信号的___和处理。
查看试卷，进入试卷练习
微信扫一扫，开始刷题
相关试题
【单选题】
电阻器反映导体对电流起阻碍作用的大小，简称___。
A. 电动势
B. 功率
C. 电阻率
D. 电阻
【单选题】
___反映了在不含电源的一段电路中，电流与这段电路两端的电压及电阻的关系。
A. 欧姆定律
B. 楞次定律
C. 部分电路欧姆定律
D. 全欧姆定律
【单选题】
并联电路中的总电流等于各电阻中的___。
A. 倒数之和
B. 相等
C. 电流之和
D. 分配的电流与各电阻值成正比
【单选题】
串联电路中流过每个电阻的电流都___。
A. 电流之和
B. 相等
C. 等于各电阻流过的电流之和
D. 分配的电流与各电阻值成正比
【单选题】
___的一端连在电路中的一点，另一端也同时连在另一点，使每个电阻两端都承受相同的电压，这种联结方式叫电阻的并联。
A. 两个相同电阻
B. 一大一小电阻
C. 几个相同大小的电阻
D. 几个电阻
【单选题】
___的电阻首尾依次相连，中间无分支的联结方式叫电阻的串联。
A. 两个或两个以上
B. 两个
C. 两个以上
D. 一个或一个以上
【单选题】
电流流过负载时，负载将电能转换成___。
A. 机械能
B. 热能
C. 光能
D. 其他形式的能
【单选题】
电功的数学表达式不正确的是___。
A. W=Ut/R2t
B. W=UIt
C. W=U2t/Rt
D. W=I2Rt
【单选题】
测量电压时，电压表应与被测电路___。
【单选题】
测量电流时,万用表的接线方法与直流电流表一样，应把万用表___在电路中。测量直流电压时，应把万用表与被测电路并联。
【单选题】
串联电路中各电阻两端电压的关系是___。
A. 各电阻两端电压相等
B. 阻值越小两端电压越高
C. 阻值越大两端电压越高
【单选题】
确定正弦量的三要素为 ___。
A. 相位、初相位、相位差
B. 最大值、频率、初相角
C. 周期、频率、角频率
【单选题】
当电压为5V时,导体的电阻值为5欧,那么当电阻两端电压为2V时,电阻值为___欧。
【单选题】
对称负载接成星形时,三相总电流___。
A. 等于零
B. 等于其中一相电流的三倍
C. 等于其中一相电流。
【单选题】
一段有源支路如图1所示，AB两端的电压UAB为___。
A. 10 V
B. —2V
C. 2V
D. —10V
【单选题】
如图2电路中，等效电阻=___
A. 150Ω
B. 900Ω
C. 600Ω
D. 100Ω
【单选题】
电流表的读数是4A，则电路中电流表的读数是 ___
【单选题】
在R、L、C串联电路中，已知＝3Ω，＝5Ω，＝8Ω，则电路的性质为 ___。
A. 感性
B. 容性
C. 阻性
D. 不能确定
【单选题】
工业生产中大量的设备均为感性负载，功率因数往往很低，常采取___的方法来提高电网的功率因数。
A. 并联电容
B. 串联电容
C. 串联电感
D. 并联电感
【单选题】
交流电压表及电流表指示的数值是___
A. 平均值
B. 有效值
C. 最大值
D. 瞬时值
【单选题】
RLC串联电路发生谐振，，R=10Ω，Ω，则谐振时的感抗为___
A. 10Ω
B. 40Ω
C. 20Ω
D. 30Ω
【单选题】
RL从电路获得最大功率，此时RL=___。
【单选题】
使用电解电容时___。
A. 负极接高电位，正极接低电位
B. 正极接高电位，负极接低电位
C. 正极接高电位，负极也可以接高电位
D. 不分正负极
【单选题】
开关接1时，电压表的读数为___。
A. 0V
B. 0.2V
C. 1.96V
D. 2V
【单选题】
开关接2时，电流表的电流为___。
A. 0A
B. 10A
C. 0.2A
D. 约等于0.2A
【单选题】
开关接1时，电流表中流过的短路电流为___。
A. 0A
B. 0.2A
C. 10A
D. 约等于0.2A
【单选题】
正弦交流电常用的表达方法有___。
A. 解析式表示法
B. 波形图表示法
C. 相量表示法
D. 以上都是
【单选题】
电感两端的电压相位超前电流___。
A. 90°
B. 180°
C. 360°
D. 30°
【单选题】
电容两端的电压相位滞后电流___。
A. 30°
B. 90°
C. 180°
D. 360°
【单选题】
应用戴维南定理求含源二端网络的输入等效电阻是将网络内各电动势___
【单选题】
LC 选频振荡电路，当电路频率等于谐振频率时，电路性质为___。
A. 电阻性
B. 感性
C. 容性
D. 纯电容性
【单选题】
阻值为4Ω的电阻和容抗为3Ω的电容串联，总复数阻抗为___
A. 3+j4
B. 3-j4
C. 4+j3
D. 4-j3
【单选题】
电动势为10V，内阻为2Ω的电压源变换成电流源时，电流源的电流和内阻是___
A. 10A，2Ω
B. 20A，2Ω
C. 5A，2Ω
D. 2A，5Ω
【单选题】
电流为5A，内阻为2Ω的电流源变换成一个电压源时，电压源的电动势和内阻为___
A. 10V，2Ω
B. 2.5V，2Ω
C. 0.4V，2Ω
D. 4V，2Ω
【单选题】
额定电压都为220V的40W、60W、100W三灯泡串联在220V的电源中，它们的发热量由大到小排列为___
A. 100W 60W 40W
B. 40W 60W 100W
C. 100W 40W 60W
D. 60W 100W 40W
【单选题】
在正弦交流电的解析式i=ImSin(ωt +φ)中，φ表示___
A. 频率
B. 相位
C. 初相位
D. 相位差
【单选题】
正弦交流电压u=100Sin(628t + 600)V，它的最大值为___。
A. 100 V
B. 100 V
C. 60V
D. 628 V
【单选题】
能表示容性电路电压与电流关系的相量图是___。
推荐试题
【单选题】
John Smith is _____ honest young man.___
【单选题】
She __________ in wearing that old – fashioned hat.___
A. insists
B. persists
C. assists
D. consists
【单选题】
Some of the meat came from Canada. How about________？___
A. another
B. the other
C. others
D. the rest
【单选题】
I have brought you ___ flowers for your birthday. ___
A. few
B. a few
C. little
D. a little
【单选题】
I have also experienced many adventures, but nothing that I have seen ___what you have described. ___
A. compares
B. relates
C. resembles
D. assembles
【单选题】
That young man has made so much noise that he ___ not have been allowed attend the concert. ___
A. could
B. must
C. would
D. should
【单选题】
“What is Mary doing at home?” “She is playing ____.”___
A. a piano
B. her piano
C. piano
D. the piano
【单选题】
I’m busy now ,ask him to see me ____ time.___
A. the other
B. some other
C. other
D. another
【单选题】
The child took a spoonful and tasted it carefully __________ it was hot.___
A. in case
B. provided
C. if
D. unless
【单选题】
The French pianist who had been praised very highly __________ to be a great disappointment. ___
A. turned off
B. turned up
C. turned out
D. turned down
【单选题】
“Shall I turn on the television?” – “No, I’d rather not __________ television tonight.”___
A. have watched
B. to watch
C. watch
D. for watching
【单选题】
They said that they had made up their minds to ____the task in spite of the extremely difficult conditions.___
A. carry on
B. carry off
C. carry away
D. carry forward
【单选题】
The two girls are getting on very well and share with each other. ___
A. little
B. much
C. some
D. none
【单选题】
The teacher said that the classroom was empty __________ a few chairs.___
A. but for
B. except for
C. apart from
D. besides
【单选题】
______you choose， make sure that it is a good one. ___
A. What
B. Wherever
C. Whichever
D. Which
【单选题】
Vingo was released from prison_____the successful efforts of his friends to prove his innocence. ___
A. according to
B. as a result of
C. for reasons of
D. with the help of
【单选题】
Entering the room， I found my father __ at the desk and ___ something .___
A. seat... write
B. seated ... wrote
C. seated ... writing
D. seating ... writing
【单选题】
Cake __________ of flour, sugar, egg and some other ingredients. ___
A. contained
B. consists
C. includes
D. composed
【单选题】
Mr. Peter wanted Steve to take half the money, but Steve did not __________ it. ___
A. obtain
B. achieve
C. accept
D. receive
【单选题】
I'd like to take my picture ________stands a high tower. ___
A. where
B. which
C. that
D. there
【单选题】
__________ the English examination I would have gone to the concert last Saturday. ___
A. But for
B. As for
C. In spite of
D. Because of
【单选题】
Cars moved very slowly in the 1920s, but they ______move more quickly than in 1910.___
A. were to can
B. did
C. will
D. can
【单选题】
The little girl needs __________ after her shock. ___
A. being comforted
B. be comforted
C. comforting
D. comforted
【单选题】
The __________ horse ran away from the fire.___
A. having frightened
B. frightening
C. frightened
D. frighten
【单选题】
He is __________ of an actor. ___
A. anybody
B. anything
C. somebody
D. something
【单选题】
You can take ______ seat you like. ___
A. no matter what
B. no matter which
C. what
D. whichever
【单选题】
He changed his name， _____ that nobody would find out what he had done before. ___
A. having thought
B. to think
C. thinks
D. thinking
【单选题】
----- _______is your English teacher？ ----- The one in red. ___
A. who
B. which
C. what
D. where
【单选题】
Can you give me a light for my cigarette? I have ____my matches.___
A. got out of
B. got rid of
C. got away with
D. run out of
【单选题】
Then the speaker __________ the various factors leading to the present economic crisis.___
A. went for
B. went after
C. went into
D. went on
【单选题】
I know Jonathan quite well and never doubt_____ he can do a good job of it___.
A. whether
B. that
C. when
D. what
【单选题】
I'm afraid it ______ tomorrow, but who knows?___
A. may have rained
B. might rain
C. would rain
D. ought to rain
【单选题】
He has spent ____money on his new house.___
A. a large number of
B. the number of
C. lots of
D. numbers of
【单选题】
This is the hotel __________ I like to stay.___
A. in which
B. at which
C. to which
D. at that
【单选题】
Would you mind keeping a（n）__________on the house for us while we are away？___
A. eye
B. /look
C. hand
D. view
【单选题】
He suggested the sports meet be _______because of the bad weather. ___
A. put away
B. put up
C. put down
D. put off
【单选题】
If the weather is __________ suitable, we will play the football match on Tuesday. ___
A. by means of
B. by any means
C. by no means
D. by all means
【单选题】
_____________is one of the five working languages at U.N. , which _______ are very proud of.___
A. The Chinese, the Chinese
B. Chinese language, Chinese
C. Chinese, the Chinese
D. Chinese language, the Chinese
【单选题】
The war lasted so long that people were tired of it. Everyday there was large crowds of demonstrators _____against the war.___
A. protecting
B. prescribing
C. protesting
D. prosecuting
【单选题】
Tom is so talkative. I’m sure you'll soon get tired ________ him.___
A. of
B. with
C. at
D. on
