機電專業(yè)英語第2版14Unit14

1、1電阻電容和電感 徐存善主編 徐存善主編 徐存善主編 If a battery is connected across a conducting material，a certain amount of current will flow through the material. This current is dependent on the voltage of the battery, on the dimensions of the sample, and on the conductivity of the material itself.1 The opposition to c

2、urrent is called electrical resistance and is represented by the letter symbol R. The unit of resistance is the ohm, a term that is often expressed by using .One ohm is defined as that amount of resistance that will limit the current in a conductor is one ampere when the voltage applied to the condu

3、ctor is one volt. Larger amounts of resistance are commonly expressed in kiloohm (K) and in megohm (M). Resistors 電阻電阻 假若將電池連接在導電材料上，一定數(shù)量的電流將流過此材料，流過材料的電流取決于電池的電壓、材料的截面積和材料自身的電阻率。對電流的阻力叫電阻，用字母符號R表示。電阻的單位是歐姆通常用表示。l歐姆的定義為：當加到導體上的電壓為l伏特時，將導體中的電流限制在1安培所需要的電阻值。較大的電阻值常用千歐(K)和百萬歐姆(M)表示。 徐存善主編 The resistors

4、 are made from carbon mixtures, metal films, or resistance wire and have two connecting wires attached. Variable resistors, with an adjustable sliding contact arm, are often used to control volume on radios and television sets. 電阻可以由碳混合物、金屬薄膜或電阻絲制成，它有兩個連線接頭。常常用帶有滑動臂的可變電阻器來控制收音機和電視機的音量。 徐存善主編 Electri

5、cal energy can be stored in an electric field. The device capable of doing this is called a capacitor or a condenser. Capacitors consist of two metal plates that are separated by all insulating material.2 If a battery is connected to both plates, an electric charge will flow for a short time and acc

6、umulate on each plate. If the battery is disconnected，the capacitor retains the charge and the voltage associated with it.3Capacitors 電容器電容器 電能可以儲存在電場中，能夠儲存電能的裝置叫電容器。電容器是由被絕緣材料分開的兩個金屬板組成。如果電池被連接在兩個金屬板上，電荷將經(jīng)過很短的流動而匯集在一個電極板上。假若斷開電池，電容器將保持電荷以及與電荷相關(guān)的電壓。 徐存善主編 The ability of a capacitor to store electric

7、al energy is termed capacitance. The capacitance is directly proportional to the dielectric constant of the material and to the area of the plates and inversely to the distance of the plates.4 It is measured in farads .When a changer of one volt per second across it causes the current of one ampere

8、to flow, the condenser is said to have the capacitance of one farad. However, farad is too large a unit to be used in radio calculation, so microfarad (10-6farads) and the picofarad (10-12farads) are generally used. 電容器儲存電能的能力叫電容。電容器的電容量與介質(zhì)的介電常數(shù)及平板的面積成正比，與平板間的距離成反比，其大小用法拉表示。當電容器兩端的電壓以每秒1伏的速率變化，產(chǎn)生的電流

9、為1安培，就稱電容器的電容量為1法拉。在無線電方面的計算中，法拉的單位太大，因此常用微法(法拉)和皮法(法拉)。 徐存善主編 Inductors consist of a conducting wire wound into the form of a coil. When a current passes through the coil, a magnetic field is set up around it that tends to oppose rapid changes in current intensity.5 All coils have inductance Induct

10、or 電感電感 電感是由繞成線圈形狀的導線組成。當電流通過線圈時，在線圈周圍將產(chǎn)生磁場，它將阻止電流的快速變化。一切線圈，都有電感。 徐存善主編 A coil of many turns will have more inductance than one of few turns. Also if a coil is placed on an iron core its inductance will be greater than it was without the magnetic core. The unit of induct- ance The unit of inductanc

11、e is the henry. A coil has an inductance of one henry if an induced emf of one volt is induced in the coil when the current through it changes at the rate of one ampere par second.6 Values of inductance used in radio equipment vary over a wide range. 匝數(shù)多的線圈比匝數(shù)少的線圈電感更大。而且，假若線圈中放一個鐵芯它的電感將比沒有鐵芯的線圈的電感更大

12、。電感的單位是亨利。當流過線圈的電流以每秒1安培的速度變化時，如果線圈中感應(yīng)出1伏特感應(yīng)電動勢，那么，線圈的電感就是1亨利。用于無線電設(shè)備的電感值的變化范圍很大。 徐存善主編 capacitor kpsit n. 電容器 capacitance kpsitns n. 電容；電流容量 inductor indkt n. 授職者；感應(yīng)器 inductance indktns n. 感應(yīng)系數(shù)；自感應(yīng)；電感 dimension dimenn, dai- n. 維；尺寸；vt. 標出尺寸adj. 規(guī)格的 conductivity ,kndktiviti n. 傳導性；導電性；傳導率 opposition

13、 ,pzin n. 反對；敵對；相反；反對派 carbon ka:bn n. 碳；碳棒；復寫紙 adj. 碳的；碳處理的 film film n. 膠卷；薄膜；輕煙；膜層vi. 生薄膜； volume vlju:m n. 體積；卷；冊；音量；大量；adj. 大量的 徐存善主編wire wai n. 金屬絲；電線；電報 vt. 拍電報；給裝電線condenser kndens n.冷凝器；壓縮器；聚合器；電容器proportional prup:nl adj. 成比例的；相稱的，n. 比例項insulate insjuleit vt. 隔離，使孤立；物使絕緣，使隔熱insulating adj.

14、 絕緣的；隔熱的（insulate的ing形式）accumulate kju:mjuleit vi. 累積；積聚 vt. 積攢disconnect ,disknekt vt. 拆開，使分離 vi. 斷開retain ritein vt. 保持；雇；記住dielectric ,daiilektrik adj. 非傳導性的；誘電性的 n. 電介質(zhì)；絕緣體inversely inv:sli adv. 倒轉(zhuǎn)地；相反地；反比例地 徐存善主編farad frd n. 法拉（電容單位）microfarad ,maikrufrd n. 微法拉（電容量的實用單位）picofarad paiku,frd n. 微

15、微法拉（百億分之一法拉）coil kil vt. 盤繞，把卷成圈 vi. 成圈狀 n. 卷；線圈intensity intensti n. 強烈；強度；亮度；緊張；集中程度 core k: n. 核心；果心；要點；磁心 (iron core 鐵芯)induced indju:st adj. 感應(yīng)的；引誘的（induce的過去分詞）henry henri n.亨(利) 電感單位，略作 H pl. henrys, henries 徐存善主編variable resistor 可變電阻器sliding contact 滑動觸點dielectric constant 介電常數(shù)，電容率magnetic

16、field 磁場emf abbr. n. 電動勢 (Electromotive Force) 徐存善主編 1. capacitance kpsitns n. 電容；電流容量；機械容量 1) related phrases： input capacitance 輸入電容 equivalent capacitance 等效電容 capacitance coupling 電容耦合 capacitance relay 電容式繼電器 shant capacitance 分流電容；并聯(lián)電容 anode capacitance 陽極電容 how they are applied in electronic

17、industry. 徐存善主編2）Features: High voltage, small collector output capacitance. 特點:耐壓高,集電極輸出電容小。3）Are there any precautions when adjusting the capacitance value? 調(diào)整電容值時有哪些注意事項?4）The formula of capacitance and voltage dependence of power has been educed. 推導出了功率隨電容和電壓變化的計算公式。 徐存善主編2dimension n. 維；尺寸；容積 v

18、t. 標出尺寸adj. 規(guī)格的1) related phrases： angular dimension 角度標注 ；角度大小 linear dimension 線性尺寸 vertical dimension 垂直尺度 fit dimension 配合尺寸 under dimension 尺寸過小 dimension scale 標注比例 徐存善主編2）Length is one dimension, and width is another. 長是一種度量，寬又是一種度量。3) The problem of the vehicle velocity detection is resolved

19、 by one dimension video tracing. 通過一維視頻跟蹤的方式，解決了車輛速度檢測的難題。4) The financial dimension to market high-quality products, quality service to win customers. 維融以優(yōu)質(zhì)的產(chǎn)品占領(lǐng)市場，以優(yōu)質(zhì)的服務(wù)贏得了客戶。 徐存善主編3. volume n. 體積；卷；音量；大量；adj. 大量的 vt. 把收集成卷1) related phrases： volume label 卷標號 bound volume 合訂本 volume control 播放控制臺

20、volume fraction 體積分率；容積比 critical volume 臨界容積 stroke volume 沖程容積；心搏量 徐存善主編2）The progress schedule compiled on the basis of volume production. 根據(jù)批量產(chǎn)品生產(chǎn)預(yù)定時間表編制的進度計劃；3）Large volume of data were gathered. 人們收集了大量的資料。4）We buy in volume and contract early to get the best prices. 大宗采購和盡早簽訂合同以獲得最低貨源價格。 徐存善主

21、編4accumulate kju:mjuleit vi. 累積；積聚 vt. 積攢1) related phrases： accumulate experience 獲取經(jīng)驗 accumulate points 積分 accumulate pick 多重選擇 accumulate funds 積累資金 accumulate dose 總劑量，累計劑量 徐存善主編2) When we accumulate more and more such differences between Chinese and English consciously, we will think in English

22、 when we speak English. 當我們有意識地積累了越來越多的類似的英漢差異之時，我們就開始用英語思維來表達事物了。3）Overall, therefore, the country did not accumulate substantial foreign currency reserves. 因此，總體來看，中國沒有積累很大的外匯儲備。4）Accumulate and summarize all kinds of index completed. Do the basic and preparation job of financial budget. 積累總結(jié)各項指標完

23、成情況的資料，做好財務(wù)預(yù)算的基礎(chǔ)準備工作。 徐存善主編5intensity intensti n. 強烈；強度；亮度；緊張；集中程度1) related phrases： field intensity 磁場強度 earthquake intensity 地震強度 radiant intensity 發(fā)光度, 輻射率, 輻射強度 loading intensity 荷載強度 intensity of market position 市場地位的集中程度 徐存善主編2) Compact, high magnetic induction intensity and long coil service

24、 life. 結(jié)構(gòu)緊湊，磁感應(yīng)強度高，線圈使用壽命長。3) This reduces the labor intensity, reduce pollution, conserve water resources. 這就降低了勞動強度、減少污染、節(jié)約水資源。4) Compact, high magnetic induction intensity and long coil service life. 結(jié)構(gòu)緊湊，磁感應(yīng)強度高，線圈使用壽命長。 徐存善主編6.induced indju:st adj. 感應(yīng)的；v. 引誘；說服（induce的過去分詞) 1) related phrases： i

25、nduced circuit 感應(yīng)電路； induced current 感生/應(yīng)電流； induced radiation 感應(yīng)(生)放射性； induced failure 誘發(fā)故障； induced operation 誘導運算 徐存善主編2）Nausea and dizziness induced by motion, as in travel by aircraft, car, or ship. 暈船（車）：由運動引起的惡心和眩暈，如乘飛機、小汽車或輪船。3）The road traffic accidents induced by fatigue driving will lead

26、 to severe personal casualty and property loss. 疲勞駕駛引發(fā)的道路交通事故導致了嚴重的人身傷亡和財產(chǎn)損失。 徐存善主編7iron core：鐵芯 magnetic core：磁芯 core k: n. 果心,核心,要點 vt. 挖去(水果的)果心 1) related phrases： cable core 電纜芯線；電纜心 core diameter 芯樣直徑；根徑 core pin 心型梢；中心銷 core competence/competenc 核心能力 ；關(guān)鍵才能 徐存善主編2）The earth have a core and a m

27、antle around it. 地球的中心是地核，地核的周圍是地幔。3）Team spirit is the core of enterprise culture. 團隊精神，是企業(yè)文化的核心。4）The monopoly pricing power is the core meaning. 壟斷最核心的意義就是定價權(quán)。5）At the core of competitiveness, like how to attract new competitiveness. 在核心競爭力不足的時候，就想怎么吸引新的競爭力。Language points 徐存善主編 1.This current is

28、 dependent on the voltage of the battery, on the dimensions of the sample，and on the conductivity of the material itself. 流過材料的電流取決于電池的電壓、材料的截面積和材料自身的電阻率。 句中be dependent (on)：“由決定，取決于”，又如： 1) Seating load and tightness is dependent on back pressure. 閥座密封負載和緊密性與反壓力相關(guān)。Language points 徐存善主編 2) Tourism

29、is a resource and the environment is heavily dependent on the industry. 旅游業(yè)是一個對資源和環(huán)境嚴重依賴的行業(yè)。 3) May you find enough inner strength to determine your own worth by yourself, and not be dependent on anothers judgments of your accomplishments. 愿你能充分發(fā)掘自身潛能，以決定你的價值所在，不要讓別人的評判埋了你的成績。Language points 徐存善主編2.

30、 be defined as：“被定義為”，后接賓語，或“that”引導的賓語從句。 如： 1）One ohm is defined as that amount of resistance that will limit the current in a conductor is one ampere when the voltage applied to the conductor is one volt. l歐姆的定義為：當加到導體上的電壓為l伏特時，將導體中的電流限制在1安培所需要的電阻值。 句中第一個that作定語，第二個that引導定語從句，該從句 本身包含了一個when引導的時時

31、間狀語從句。Language points 徐存善主編2）A molecule may be defined as the smallest particle of matter that can exist without changing its nature. 分子可以被定義為物質(zhì)在不改變其性質(zhì)的情況下而能存在的物質(zhì)的最小粒子。3) Motion may be defined as a continuous change of a body in position with respect to some other body or bodies at rest. 運動可定義為一個物體相

32、對于另一個或幾個靜止物體在位置上的連續(xù)變化。Language points 徐存善主編3. Capacitors consist of two metal plates that are separated by all insulating material. 電容器是由被絕緣材料分開的兩個金屬板組成。 句中that引導定語從句，修飾two metal plates，consist of表示“由組成”，又如： 1）Audit risks consist of intrinsic risk, control risk and examination risk. 審計風險由固有風險、控制風險和檢

33、查風險構(gòu)成。 2）Modern wind farms consist of turbines that generate electricity. 現(xiàn)代風力農(nóng)場由發(fā)電的渦輪機組成。Language points 徐存善主編4. If the battery is disconnected，the capacitor retains the charge and the voltage associated with it. 如果斷開電池，電容器將保持電荷以及與電荷相關(guān)的電壓。 句中retain表示“保持；雇；記住”的意思。又如： 1）Help your skin retain moisture

34、. 幫助皮膚保持水分。 2）Retain your original receipt as proof of purchase. 請保留您的原始發(fā)票作為購買證明。 3）Money has two functions, one is to retain the value of wealth, the other is an exchange value of the wealth. 金錢有兩個職能，一個是保留財富價值，一個是交換財富價值。Language points 徐存善主編5. The capacitance is directly proportional to the dielect

35、ric constant of the material and to the area of the plates and inversely to the distance of the plates. 電容器的電容量與介質(zhì)的介電常數(shù)及平板的面積成正比,與平板間的距離成反比。 a）be directly proportional to：“與成正比” b）be inversely proportional to：“與成反比” 又如： 1) The resistance of a thin film/coating is directly proportional to the resisti

36、vity, and inversely proportional to the thickness. 薄膜鍍膜的電阻與該鍍鏌的電阻系數(shù)成正比,與厚度成反比.Language points 徐存善主編2) The magnitude of the force is found to be inversely proportional to the distance between the conductors. 人們發(fā)現(xiàn)力的大小與施力者之間的距離成反比。 6. When a current passes through the coil，a magnetic field is set up ar

37、ound it that tends to oppose rapid changes in current intensity 當電流通過線圈時，在線圈周圍將產(chǎn)生磁場，它將對抗電流的快速變化。 句中that引導定語從句，修飾a magnetic field，it指代the coil。oppose vt. vi. 表示“ 反對；對抗，抗爭”，又如：Language points 徐存善主編1）Small banks and some state officials strongly oppose the plan. 小銀行以及某些州的官員強烈反對該方案。2）We oppose all forms

38、 of hegemonism and power politics. 反對各種形式的霸權(quán)主義和強權(quán)政治。Language points 徐存善主編7. Also if a coil is placed on an iron core its inductance will be greater than it was without the magnetic core. 而且，如果線圈中放一個鐵芯，它的電感將比沒有鐵芯的線圈的電感大。 句中than引導一個比較狀語從句。inductance indktns n. “感應(yīng)系數(shù)；自感應(yīng)；電感”，又如： 1）DC voltage is determi

39、ned by AC voltage, inductance on the AC side, and load. 直流側(cè)直流電壓是由交流電壓、電感及負載決定的。 Language points 徐存善主編2）The effects of inductance and capacitance make it necessary to carefully design all AC transmission systems. 電感和電容的影響，使人們必須精心地設(shè)計所有的交流輸電系統(tǒng)。8. A coil has an inductance of one henry if an induced emf

40、of one volt is induced in the coil when the current through it changes at the rate of one ampere per second. 當流過線圈的電流以每秒1安培的速度變化時，如果線圈中感應(yīng)出1伏特感應(yīng)電動勢，那么，線圈的電感就是1亨利。 at the rate of “以的速度/速率/比率/變化率/頻率” 又如：Language points 徐存善主編1）Income from property transactions shall be filed and taxed at the rate of 35%

41、. 財產(chǎn)交易所得按35%扣繳率申報納稅。2）Profits from occasional trade shall be filed and taxed at the rate of 30%. 一時貿(mào)易的盈余按30%扣繳率申報納稅。Exercises 徐存善主編I. Answer the following questions according to the text. 1.What is called a resistor? What is the unit of resistance? 2.What is the usage of variable resistors?The resis

42、tors are made from carbon mixtures, metal films, or resistance wire and have two connecting wires attached. The opposition to current is called electrical resistance.Variable resistors, with an adjustable sliding contact arm, are often used to control volume on radios and television sets.Exercises 徐

43、存善主編3. What is called a condenser? Which elements do condensers consist of?4. How to define one farad of the capacitance? The device capable of doing this is called a capacitor or a condenser. Capacitors consist of two metal plates that are separated by all insulating material.When a changer of one

44、volt per second across it causes the current of one ampere to flow, the condenser is said to have the capacitance of one farad.Exercises 徐存善主編5. What are inductors made up of? How to define one henry of an inductance? Inductors consist of a conducting wire wound into the form of a coil. A coil has a

45、n inductance of one henry if an induced emf of one volt is induced in the coil when the current through it changes at the rate of one ampere par second.Exercises 徐存善主編IIFill in the missing words according to the text 1. This current depends on the voltage of the battery, on the _ of the sample, and

46、on the _ of the material itself.2. A _is a device designed to have capacitance.3. Ohm is used as a unit of _.dimensionsconductivitycapacitorresistanceExercises 徐存善主編4. The larger is the emf, the more _ the capacitor stores5. When a changer of one volt per second across it causes the current of one a

47、mpere to flow, the _ is said to have the capacitance of one _ .6. The _ are made from carbon mixtures，metal films，or resistance wire and have two _ wires attached.capacitancecondenserfaradresistorsconnectingExercises 徐存善主編1. 可變電阻器常用來控制收音機和電視機的音量。 2.電容器存儲電能的能力叫電容。Variable resistors are often used to

48、control volume on radios and television sets.The ability of a capacitor to store electrical energy is termed capacitance. IIITranslate the following sentences into EnglishExercises 徐存善主編3. 任何電感都是由線圈組成，線圈的匝數(shù)越多，電感越大。4. 電容器的電容量與介質(zhì)的介電常數(shù)及平板的面積成正比,與平板間的距離成反比。 Inductors consist of a conducting wire wound i

49、nto the form of a coil. A coil of many turns will have more inductance than one of few turns.The capacitance is directly proportional to the dielectric constant of the material and to the area of the plates and inversely to the distance of the plates. 徐存善主編 And作連詞，用來連接詞、短語和句子，其基本意義相當于漢語的“和”、“與”、“并且”

50、。但在實際翻譯的過程中，特別是在連接兩個句子時，它的譯法很多，表達的意義可能相差甚遠。如果不考慮and 前后成分之間的邏輯關(guān)系，只用幾種基本譯法生硬套用，難免造成理解上的失誤，甚至把整個句子意思搞錯。 l. And表示原因，例如： Laser is widely used for developing many new kinds of weapons, and it penetrates almost everything. 激光廣泛用于制造各種新式武器，因為為它的穿透力很強。 徐存善主編 2. And表示因果，譬如： 1）But since a digital signal is made

51、 up of a string of simple pulses, noise stands out and easily removed. 但由于數(shù)字信號由一組簡單脈沖組成，雜音明顯，容易發(fā)現(xiàn)，因而容易排除。 2）In l945 a new type of aeroplane engine was invented, it was much lighter and powerful than earlier engines, and enabled war planes to fly faster and higher than ever. 1945年發(fā)明了一種新型的飛機發(fā)動機。它比早期發(fā)動

52、機要輕的多，功率也要大得多，因此采用這種發(fā)動機的軍用飛機比以往任何時候都飛得更快、更高。 徐存善主編 3. And表示目的，例如： It was later shown that the results of this work were by no means the ultimate，and further work has been put in hand and to provide closer control and more consistent operation in this area. 后來發(fā)現(xiàn)，這項研究工作的結(jié)果絕非已作定論，而進一步的研究工作已開始，以便在這方面提供較

53、嚴密的控制和較穩(wěn)定的操作。 4. And表示承接，譬如： In many ways, computer is more superior than human brain, and human can rule it. 在許多方面計算機超過人腦，而人卻可以控制它。 5. And表示對照，例如： 例: Motion is absolute, and stagnation is relative. 運動是絕對的，而靜止是相對的。 徐存善主編 6. And表示遞進，譬如： 例: The electronic brain calculates a thousand times quicker, and

54、 more accurately than is possible for the human being. 電腦的運算速度比人所能達到的要快1000倍，甚至更加準確。 7. And表示轉(zhuǎn)折，例如： 例: There will always be some things that are wrong, and that is nothing to be afraid of. 錯誤的東西在所難免，但并不可怕。 徐存善主編 8. And表示條件，譬如： Even if a programmer had endless patience, knowledge and foresight, stori

55、ng every relevant detail in a computer, the machines information would be useless, and the programmer knew little how to instruct it in what human beings refer to as commonsense reasoning. 即使一個編程員很有耐心、知識和遠見，把每一個有關(guān)細節(jié)都存入計算機，如果他不懂得按人類常識推理去對計算機下達指令，機器里的信息也還是沒有用途的。 9. And表示結(jié)果，例如： Operators found that the

56、 water level was too low so they turned on two additional main coolant pumps, and too much cold water flowing into the system caused the steam to condense, further destabilizing the reactor. 操作人員發(fā)現(xiàn)冷卻水的水位過低，就啟動了另外兩臺主冷卻泵，結(jié)果過量的冷卻水進入系統(tǒng)使蒸氣冷凝，反應(yīng)堆因而更不穩(wěn)定。 徐存善主編Analog Multimeter Digital Multimeter Bench-type

57、 Digital Multimeter Digital Storage Oscilloscope 徐存善主編Testing and Measuring Instruments Once a particular component is suspected of being faulty, individual tests must be then performed. And the testing and measuring instruments often to be used are as follow: Multimeter A multimeter is sometimes ca

58、lled a volt-ohmmilliammeter. Multimeters having only volt and ohm ranges are also called volt-ohmmeters. There are two main kinds of multimeters. They are mechanical handy multimeters and digital ones. Its better for learners to use handy types, because its helpful for them to be familiar with some

59、electronic principles. 測試儀器測試儀器 一旦懷疑某個元件出故障，就得單獨做些測試。常用的測試與測量儀器如下： 萬用表萬用表 萬用表有時候被稱為伏特-歐姆-毫安表。只具有電壓(伏特)和電阻檔 (歐姆)的萬用表也叫伏歐表。萬用表主要有兩種：機械指針式萬用表和數(shù)字式萬用表。初學者最好使用指針式，因為指針式萬用表有助于他們熟悉一些電子原理。 徐存善主編 Using a multimeter，you should first place it flat on a table and note if the meter pointer indicates exactly 0 at

60、the extreme left end of the black scale.1 If it doesnt read 0, turn the screw on the meter movement slowly until the proper 0 reading is realized.2 And then connect test-1ead to the otherSet the RANGE switch to the proper item and rangeInsert the test-lead plugs into the correct pair of jacks，clip o