chương 1 Nội dung: - Về kiến thức: + Số lượng từ vựng + Cấu trúc câu hỏi "what", "where", "how long/how high" + Sử dụng giới từ - Về kỹ năng: + Đọc hiểu + Đàm thoại - Về năng lực tự chủ và trách nhiệm: Tỉ mỉ, cẩn thận, chính xác. Phương pháp: - Kiến thức: Được đánh giá bằng hình thức kiểm tra viết, trắc nghiệm - Kỹ năng: Đánh giá kỹ năng đọc hiểu, đàm thoại - Về năng lực tự chủ và trách nhiệm: Đánh giá phong cách học tập 12 CHAPTER 2: ELECTRICAL MATERIALS Mã chương: MH 07- 02 Giới thiệu: Nhằm giúp sinh viên có hướng tiếp cận dễ dàng trong việc học tiếng Anh chuyên ngành Cơ điện tử, chương này giới thiệu cho sinh viên về các thuộc tính và đặc điểm kỹ thuật của các loại vật liệu điện bằng tiếng Anh. Mục tiêu: Sau khi học xong bài học này, sinh viên có kiến thức và kỹ năng về sử dụng anh ngữ: - Đọc hiểu được các thuật ngữ về vật liệu điện, điện tử bằng tiếng anh - Hiểu được các từ trong cấu tạo và nguyên lý vật liệu dẫn điện, vật liệu bán dẫn, vật liệu cách điện, vật liệu từ và các vật liệu đặc biệt khác bằng tiếng anh. - Sử dụng được thì hiện tại đơn để giao tiếp trong lĩnh vực điện bằng tiếng anh.
- Tự tin giao tiếp tiếng anh chuyên ngành trong môi trường làm việc tại doanh nghiệp - Đọc hiểu tài liệu tham khảo bằng tiếng anh trong lĩnh vực điện tử - Chủ động, tự giác trong học tập. Nội dung chính: 1. Vocabulary Resistivity (n) : Điện trở Annealing (n) : Sự tôi luyện Conducting (adj) : Dẫn điện Valence (n) : Hóa trị Category (n) : Loại Insulating (adj) : Cách điện Transmission (n) : Truyền tải Capacitor (n) : Tụ điện Distribution (n) : Phân phối Thermoplastic : Chịu nhiệt Transformer (n) : Máy biến thế Thermosetting : Phản ứng Copper (n) : Đồng nhiệt Aluminium (n) : Nhôm Elastic (adj) : Đàn hồi Coefficient (adj) : Hệ số Solvent (n) : Dung môi Variation (n) : Biến thiên Brittle (adj) : Dễ vỡ Voltage drop (n) : Điện áp rơi Repellent (adj) Không thấm Withstand (v) : Chịu đựng : nước Ductility (n) : Độ dẻo dai Molecule (n) : Phân tử Mould (v) : Đúc Elongate (v) : Giãn nở Solderability (n) : Tính dễ hàn Elasticity (n) : Độ đàn hồi Corrosion (n) : Sự ăn mòn Polymerisation Sự polymer Precision (n) : Độ chính xác : hóa Rheostat (n) : Biến trở Hysteresis (adj) : Trễ điện môi Melting (adj) : Tan chảy Saturation (n) : Bão hòa Oxidation (n) : Sự ô xy hóa Magnetization (n) : Độ từ hóa Malleable (adj) : Dẻo Curve (v) : Uốn cong Tensile (adj) : Chịu bền Coercivity (n) : Độ kháng Busbar (n) : Thanh cái Adamantine (n) : Chất adaman Brass (n) : Đồng thau Ultrahard (adj) : Siêu cứng Bronze (n) : Đồng đỏ Darkwood (n) : Gỗ cứng Constantan (n) : Hợp chất nikel Alchemical (n) : Luyện đan Fuse (n) : Cầu chì Metallurgy (n) : Luyện kim Socket (n) : Ổ cắm Alchemy (n) Thuật luyện Fluorescent : Đèn huỳnh : đan 13 tube (n) quang Bypass (v) : Đường vòng Electric bell (n) : Chuông điện Transmission Đường dây Three-core cable (n) : Dây cáp 3 lõi line (n) : truyền tải Fuse wire (n) : Dây chì Bulb (n) : Bóng đèn Copper conductor : Dây dẫn đồng Safety helmet (n) : tròn High- voltage : Dây dẫn Outlet (n) : Mũ bảo hiểm conductor(n): cao thế Earthed socket (n) Ổ điện Extension cord (n) : Dây dẫn nhánh : Ổ điện có dây Electric tool (n) : Dụng cụ điện Underfloor socket tiếp đất Thermoplastic (n) : Tính chịu nhiệt Adapter (n) : Ổ điện ẩn Meter (n) : Đồng hồ đo Voltage stabilizer : dưới sàn Electric meter (n) : Đồng hồ điện Cable clip (n) : Bộ nắn điện Cable gland (n) : Cổ cáp Plug (n) : Máy ổn áp Cable lug (n) : Đầu cốt Nẹp ống dây Phích cắm 2.1 The Simple Present Tense a. Structure To form the Present Simple Tense we use the verb's base form (go, work, speak, study).
In 3rd person singular (he, she, it), the base form of the verb takes -s/es. (Auxiliary verbs “be,” “do,” “have”, which can also be used as main verbs, are exceptions.) Affirmative form I / You / We / They + V_infinitive He/She/It + V_(s,es) Example: Electric current deals with charges in motion I go to school every day. Negative form I / You / We / They + do not /don't +V_infinitive He/She/It does not /doesn't / +V_infinitive Example: She doesn't often go to the cinema. I don't get up early at the weekend.
They don't speak English very well. Interrogative form Do + I / You / We / They + V_infinitive Does + He/She/It + V_infinitive Example: Do they speak foreign languages? Does your sister play the piano? Questions and short answers: Do you like spaghetti? Yes, I do. Does she know Bulgarian? Yes, she does. 14 No, she doesn't.
Use When we talk about things that happen repeatedly or habitually with time expressions such as always, often, sometimes, usually, seldom, on Saturdays, rarely, never, every day, etc. Example: This flow of charge creates an electric current I usually sleep late on Sunday morning. To indicate general truths, facts and scientific laws Example: The sun rises in the east. Water freezes at 0°C (32°F) 2.
Exercises Using the words in parentheses, complete the text below with the appropriate tenses, then click the “Check” button to check your answers. Every Monday, Sally (drive)…………her kids to football practice. Usually, I (work) ………………as a secretary at ABT, but this summer I (study) ……………French at a language school in Paris. That is why I am in Paris.
I hate living in Seattle because it (rain, always)………………. I'm sorry I can't hear what you (say)………………because everybody (talk) ………………so loudly. Justin (write, currently)…………………a book about his adventures in Tibet. I hope he can find a good publisher when he is finished.
Jim: Do you want to come over for dinner tonight? Denise: Oh, I'm sorry, I can't. I (go)…………………to a movie tonight with some friends. The business cards (be, normally)…………………printed by a company in New York. Their prices (be)…………………inexpensive, yet the quality of their work is quite good.
This delicious chocolate (be)……………………made by a small chocolaty in Zurich, Switzerland. Form questions Example: Where / they / to have / breakfast Where do they have breakfast? a) how / Linda / to go / to the park → ……………………………………………………………………………… b) Marie and Joe / to like / homework → ……………………………………………………………………………… c) why / you / to ride / your bike →………………………………………………………………………………. d) what / they / to eat / for breakfast → ……………………………………………………………………………… e) can / Ron / to speak / English → ……………………………………………………………………………… f) Frank / to read / comics → ……………………………………………………………………………… g) where / she / to live → ……………………………………………………………………………… 15 h) to be / Peter / from Austria → ……………………………………………………………………………. i) you / to walk / to school → …………………………………………………………………………….
j) when / his mum / to come / home → ……………………………………………………………………………… 2. Negative the sentences Example: He works on the computer. - He does not work on the computer. The children know the answer.
He is from Spain. The kite flies into the air. Kevin plays basketball. Anne and Sue carry a box.
Steve can make breakfast. → …………………………………………………………………………… Sandy washes her hair. I run to school. Mr Smith teaches French.
Conducting Materials Conducting materials are classified as low resistivity materials and high resistivity materials. Low resistivity materials: The conducting materials having resistivity between 10-8 to 10-6 ohm-m come under this category and are used in transmission and distribution lines, transformers and motor windings such as copper, aluminium, steel, … Properties: a) Low temperature coefficient: For minimum variations in voltage drop and power loss with the change in temperature, these materials should have low temperature coefficient. b) Sufficient mechanical strength: These materials must withstand the mechanical stresses developed during its use for particular applications. c) Ductility: The material to be used for conductors must be ductile so that it can be drawn and moulded into different sizes and shapes.
d) Solderability: The conducting materials are required to be joined and the joint must have minimum contact resistance. These materials must have a good solderability. e) Resistance to corrosion: The material should have a high resistance to corrosion so that it should not be corroded when used in different environmental conditions. High resistivity materials: The conducting materials having resistivity between 10-6 to 10-3 ohm-m come under this category and are used for making 16 resistance elements for heating devices, precision instruments, rheostats etc such as manganin, nichrome, mercury, platinum, carbon and tungsten, … Properties: a) Low temperature coefficient: For minimum variations in voltage drop and power loss with the change in temperature, these materials should have low temperature coefficient.
b) High melting point: These materials, which are used as heating elements should have high melting point. c) Ductility: The material to be used for conductors must be ductile so that it can be drawn and moulded into different sizes and shapes. d) Oxidation resistance: The material should have a high oxidation resistance so that it should get oxidised when used in different environmental conditions. e) High mechanical strength: These materials must withstand the mechanical stresses developed during its use for particular applications.
Copper: Aluminium: Properties Properties 1) It is reddish brown in colour. 1) Pure aluminium is silver white in 2) It is malleable and ductile and can be colour. cast, forged, rolled, drawn and machined. 2) It is a ductile metal and can be put to 3) It melts at 10830C.
a shape by rolling, drawing and forging. 4) It easily alloys with other metals. 3) It melts at 6550 C. 5) Electrical resistivity of copper is 4) It is resistant to corrosion.
5) Its tensile strength is 60MN/m2. 6) Tensile strength for copper is 210 6) It can be alloyed with other elements. 7) Annealing can soften it. 7) It is highly resistant to corrosion.
8) It has a higher thermal conductivity. 8) It is a non-magnetic material. Applications: Aluminium is widely Applications: Copper is used in used as conductor for power conductor wires, coil windings of transmission and distribution. It is used generators and transformers, cables, in overhead transmission lines, busbars, busbars etc.
Alloys of copper (like Brass, ACSR conductors etc. Bronze, Constantan, Manganin etc) are very useful for different purposes. Semiconducting Materials These are the materials, which possess the electrical resistivity in between that of conductors and insulators. They are used for the manufacture of diodes and transistors.
Also the number of valence electrons is equal to four. There is a small forbidden energy gap of about 1eV between the conduction and the valence band. Examples: germanium, silicon, selenium, etc. Properties: Substances like carbon, silicon, germanium whose electrical conductivity lies in between the conductors and insulators are known as semiconductors.
The valence band of these substances is almost filled, but the conduction band is almost empty. The forbidden energy gap between valence and conduction band is very small (1ev). Therefore comparatively a smaller electric field is required to push the valence electrons to the conduction band. This is the reason, why such materials under ordinary conditions do not conduct current and behaves as an insulator.
Even at room temperature, when some heat energy is imparted to the 17 valence electrons, a few of them cross over to the conduction band imparting minor conductivity to the semiconductors.