新思维 刘尹 学生版
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新思维小学英语1A教学计划一、指导思想:结合小学英语教学的特点,主要激发学生学习英语的兴趣,培养良好的语言学习习惯,着重培养学生英语基础语言能力和英语语感能力,循序渐进地建立起英语语言思维能力,为学生进一步学习英语打下良好基础。
二、学生基本情况分析:一年级小朋友刚接触英语,学习兴趣很浓,接受能力、模仿能力很强,学习习惯初步养成,但由于年龄的特点,注意力容易分散,所以在本学期,还有待培养学生的良好的学习习惯,训练学生的听说能力。
本班学生共41人,男生22,女生19。
学生上课时的控制能力高和思想注意力不分散,且学生刚碰触自学英语,对英语自学没基础,所以教学难度很大。
少数学生在学前班研习过一点,但大部分学生没碰触过英语,所以在今后的教学中,应当面向全体生,唤起学生自学英语的兴趣,充分调动他们的独立自主能动性、积极性,并充分发挥团队协作精神,营造互帮互助,共同自学英语的语境。
三、教学目的、任务:1、以发展儿童的口语为核心,培育儿童对英语的积极态度和良好习惯,创建和进一步增强儿童英语自学的自信心,掌控基本的英语科学知识,发展儿童的英语听闻能力和真实生活情境中运用英语的能力,全面提高儿童的综合素质。
2、帮助家长了解、掌握科学的现代家庭教育观念,促进家长的狼嚎的教育行为,增进亲子沟通,发展积极的亲子互动方式。
四、教材分析:教材既要考虑到学生刚刚开始学习英语,特设计了一些日常生活中使用频率的词句,课文中所有内容都是依据语用、语境和语义相结合的原则而呈现的,所以学生在学习时,应积极参与到老师特设的语用和语境中,掌握语句和词语的基本语义,逐步获得最基本的运用英语的能力。
五、教学措施:1、深钻教材,挖掘教材的内在联系,认真备好每节课,精心设计教案。
2、更新教育观念,明晰教师角色,创建以人为本的学生主体观,创建民主、公平、人与自然、合作的教育观,使学生在随心所欲的氛围中学至科学知识。
3、改进教学方法,提高教学效率,改变过去“满堂灌”的方式,让课堂焕发出生命的活力,在课堂上,有讲有练,精讲精练,有动有静,让学生说起来,动起来。
新思维一年级英语1b全文共3篇示例,供读者参考篇1Title: New Thinking 1st Grade English 1BIntroduction:New Thinking 1st Grade English 1B is a comprehensive textbook designed for young learners who are just starting to learn English. This textbook provides a solid foundation in English language skills, including reading, writing, listening, and speaking. With a focus on real-life communication and interactive activities, students are introduced to basic English vocabulary, grammar, and sentence structures.Chapter 1: Hello, Friends!In this chapter, students are introduced to basic greetings and introductions. They learn common phrases such as "Hello, how are you?" and "My name is…". Through fun games and activities, students practice speaking and listening skills.Chapter 2: My FamilyIn this chapter, students learn vocabulary related to family members. They are able to describe their own family members and relationships. Activities such as drawing family trees and role-playing scenarios help students apply their new vocabulary in context.Chapter 3: My SchoolThis chapter introduces school-related vocabulary such as classroom objects, subjects, and activities. Students learn how to talk about their daily routines and favorite school subjects. They also practice forming simple sentences using the present tense.Chapter 4: My HouseStudents learn vocabulary related to different rooms in a house, furniture, and household items. They practice describing their own homes and daily routines. Interactive activities like matching games and picture prompts help reinforce vocabulary retention.Chapter 5: Food and DrinkIn this chapter, students learn common food and drink items. They practice ordering food, expressing preferences, and responding to simple questions about mealtime. Role-playinggames and group discussions are used to enhance conversational skills.Chapter 6: Seasons and WeatherStudents learn vocabulary related to seasonal weather patterns. They practice describing weather conditions, clothing choices, and outdoor activities. Through hands-on activities like creating weather charts and simulating weather forecasts, students deepen their understanding of seasonal changes.Conclusion:New Thinking 1st Grade English 1B provides a solid foundation for young learners to develop their English language skills. Through engaging activities, real-life scenarios, and interactive lessons, students are able to build their vocabulary, grammar, and conversational skills. This textbook is a valuable resource for teachers and students alike in their English language learning journey.篇2Title: New Thinking 1B Grade EnglishIntroduction:New Thinking 1B Grade English is a comprehensive textbook designed for first-grade students to learn English effectively. It covers a wide range of vocabulary, grammar, and communication skills to help students build a solid foundation in the English language. This document will provide an overview of the content and key features of the textbook.Content:The textbook is divided into 12 units, each containing various themes and topics relevant to first-grade students. The units are structured to introduce new vocabulary and grammar concepts gradually, allowing students to grasp the language step by step.One of the key highlights of the textbook is the focus on communication skills. Students are encouraged to engage in interactive activities, such as role-plays, group discussions, and pair work, to practice using the language in real-life situations. This helps students develop their speaking and listening skills, as well as their confidence in using English.In addition to vocabulary and grammar, the textbook also incorporates reading and writing exercises to enhance students' comprehension and expression abilities. The reading passages are carefully selected to be age-appropriate and engaging, whilethe writing tasks are designed to promote creativity and critical thinking.Key Features:- Colorful illustrations and multimedia resources to support visual learning- Audio recordings of dialogues and vocabulary to improve listening skills- Interactive activities and games to make learning enjoyable and effective- Progress tests and assessments to measure students' learning outcomes- Teacher's guide with lesson plans and additional resources for classroom instructionConclusion:New Thinking 1B Grade English is a comprehensive and engaging textbook that provides students with a solid foundation in the English language. With its focus on communication skills and interactive learning activities, the textbook is designed to meet the needs of first-grade studentsand help them succeed in their English language learning journey.篇3New Concept English 1b is a textbook designed for first graders who are learning English as a second language. This book is a part of the New Concept English series, which aims to provide young learners with a comprehensive and interactive way to learn English.The content of New Concept English 1b is divided into 12 units, each covering different topics such as greetings, colors, family members, animals, weather, and food. Each unit includes vocabulary, grammar, reading comprehension, listening exercises, and speaking activities to help students practice their language skills in a variety of ways.One of the key features of New Concept English 1b is its use of colorful illustrations and engaging activities to make learning fun and engaging for young learners. The book also includes audio recordings of the vocabulary and dialogues, which provide students with the opportunity to practice listening and pronunciation skills.In addition, New Concept English 1b includes a variety of interactive activities such as puzzles, matching games, androle-playing exercises that allow students to practice what they have learned in a fun and engaging way. The book also includes regular review sections to help students consolidate their learning and track their progress.Overall, New Concept English 1b is a comprehensive and engaging textbook that provides young learners with the tools they need to develop their English language skills. By using a combination of interactive activities, colorful illustrations, and audio recordings, this book offers a dynamic and effective way for students to learn English in an enjoyable and engaging way.。
剑桥新思维英语青少版1 第三单元全文共3篇示例,供读者参考篇1Unit 3 Talking about routinesIn Unit 3 of Cambridge New Thinking English Junior Version 1, students learn how to talk about daily routines. This unit focuses on vocabulary related to activities we do every day, such as getting up, brushing teeth, having breakfast, going to school, etc. Students also learn how to use present simple tense to describe routines and frequency adverbs to talk about how often they do certain activities.Vocabulary:The vocabulary in this unit includes words related to daily routines and activities, such as wake up, get dressed, brush teeth, have breakfast, go to school, do homework, play sports, etc. By learning these words, students will be able to describe their daily routines in English.Grammar:In this unit, students learn how to use the present simple tense to talk about habitual actions and routines. They also learn how to use frequency adverbs like always, often, sometimes, rarely, and never to talk about how often they do certain activities. For example, "I always wake up at 7 am," or "I rarely play sports on weekends."Exercises:To practice the vocabulary and grammar learned in Unit 3, students can do exercises that involve writing sentences about their daily routines, filling in the blanks with the correct verbs, and answering questions about their habits using frequency adverbs. These exercises help reinforce the material learned in the unit and improve students' speaking and writing skills.Role-plays:Role-plays are another way for students to practice talking about routines. In pairs or groups, students can role-play typical daily routines, such as getting ready for school in the morning or doing homework in the afternoon. This activity helps students practice using the vocabulary and grammar in a more natural and conversational way.Overall, Unit 3 of Cambridge New Thinking English Junior Version 1 is a comprehensive and engaging unit that helps students talk about their daily routines in English. By learning the vocabulary, grammar, and practicing through exercises and role-plays, students will improve their English communication skills and be able to describe their routines with confidence.篇2Cambridge New Thinking English for Young Learners Level 1 Unit 3Unit 3 of the Cambridge New Thinking English for Young Learners Level 1 textbook focuses on the theme of "My Family." In this unit, students will learn vocabulary related to family members, their roles, and their relationships. They will also practice using possessive pronouns and describing family members using adjectives.The unit starts with a warm-up activity where students sing a song about family members. This helps to introduce the topic and set the tone for the unit. The vocabulary section introduces students to words such as father, mother, brother, sister, grandmother, and grandfather. Through flashcards, pictures, andinteractive activities, students are encouraged to learn the new words and understand their meanings.Next, students learn how to use possessive pronouns to talk about their family members. They practice using sentences like "This is my father" or "That is my sister." Through repetition and practice exercises, students become more confident in using possessive pronouns correctly.The unit also includes activities that help students describe their family members. For example, they may be asked to describe their father as tall, their mother as kind, or their brother as funny. This helps students expand their vocabulary and practice using adjectives to describe people.In addition to vocabulary and grammar practice, Unit 3 also includes listening and speaking activities. Students listen to conversations between family members and answer questions about them. They also practice speaking about their own family members, using the vocabulary and grammar structures they have learned.Overall, Unit 3 of the Cambridge New Thinking English for Young Learners Level 1 textbook provides a comprehensive introduction to the topic of family. Through a variety of activities, students learn vocabulary, grammar, and speaking skills relatedto family members. This unit helps students build a strong foundation in English while engaging with a topic that is familiar and relevant to their lives.篇3Unit 3: Around the CityIn Unit 3 of Cambridge New Thinking English Junior, students will learn how to talk about different places and landmarks in the city. This unit focuses on expanding vocabulary related to transportation, buildings, and places around the city, as well as practicing conversations and role-plays to improve communication skills.Vocabulary:- Transportation: students will learn words related to different modes of transportation such as bus, subway, taxi, and bicycle.- Buildings: students will be introduced to vocabulary relating to different types of buildings, such as library, school, museum, and hospital.- Places around the city: students will learn the names of various places such as park, shopping center, market, and cafe.Grammar:- Prepositions of place: students will practice using prepositions such as at, in, on, next to, and between to describe the location of places in the city.- Present continuous tense: students will learn how to form and use the present continuous tense to talk about actions happening at the moment.Activities:- Vocabulary games: students will engage in fun games to practice and reinforce new vocabulary related to the city.- Role-plays: students will participate in role-plays to practice conversations about going to different places in the city and using transportation.- City tour project: students will work in groups to plan a city tour, deciding which places to visit and how to get there, while using the vocabulary and grammar structures learned in the unit.Overall, Unit 3 of Cambridge New Thinking English Junior provides students with the opportunity to build their vocabulary, improve their grammar skills, and practice speaking in real-life situations related to the city. By the end of the unit, students willbe able to confidently talk about different places and navigate their way around the city in English.。
外研新思维英语少儿版go inside forlessonsThe world of education is constantly evolving and adapting to the changing needs and demands of students. In recent years, the focus has shifted towards a more personalized and immersive approach to learning, particularly in the field of language education. One such innovative program that has gained significant attention is the "外研新思维英语少儿版go inside for lessons" (hereinafter referred to as "the Program").The Program is a groundbreaking initiative developed by the renowned language education institution, 外研社 (Foreign Language Teaching and Research Press). It is designed to provide a comprehensive and engaging learning experience for young English language learners, empowering them to develop their linguistic skills in a dynamic and interactive environment.At the heart of the Program lies a unique approach that encourages students to "go inside for lessons." This phrase encapsulates the corephilosophy of the Program, which emphasizes the importance of immersing students in an authentic and enriching learning environment. Rather than traditional classroom-based instruction, the Program offers a multifaceted learning experience that combines interactive activities, digital resources, and personalized guidance.One of the key features of the Program is its emphasis on creating a stimulating and engaging learning space. Instead of the typical classroom setup, the Program's learning centers are designed to resemble cozy and inviting living rooms or study spaces. This setting aims to foster a sense of comfort and familiarity, allowing students to feel at ease and more receptive to the learning process.Within these inviting spaces, students are encouraged to actively participate in a variety of interactive activities. From role-playing scenarios and group discussions to multimedia presentations and hands-on projects, the Program offers a dynamic and immersive learning experience that caters to diverse learning styles and preferences.The use of digital resources is another integral component of the Program. Leveraging the power of technology, the Program integrates a range of digital tools and platforms to enhance the learning experience. Students have access to interactive language learning apps, virtual reality simulations, and online resources thatprovide a seamless and engaging learning journey.Personalized guidance is another hallmark of the Program. Each student is assigned a dedicated learning coach who closely monitors their progress and provides individualized support. These coaches work closely with students to identify their strengths, address their challenges, and develop customized learning plans to maximize their language proficiency.One of the standout features of the Program is its emphasis on fostering a sense of community and collaboration among students. The learning centers are designed to facilitate group activities and peer-to-peer interactions, encouraging students to learn from one another, share their experiences, and build meaningful connections.This collaborative approach not only enhances the learning experience but also helps to cultivate essential 21st-century skills, such as communication, problem-solving, and critical thinking. By engaging in group discussions, role-playing exercises, and project-based learning, students develop a deeper understanding of the language and its practical applications.Furthermore, the Program places a strong emphasis on cultural immersion and global awareness. Through a variety of cultural activities, field trips, and international exchange programs, studentsare exposed to diverse perspectives and gain a deeper appreciation for the richness of different cultures.This holistic approach to language education not only enhances the students' linguistic abilities but also fosters a well-rounded and globally-minded individual. By integrating cultural elements into the learning process, the Program aims to cultivate a deeper understanding and appreciation for the interconnectedness of the world.One of the most remarkable aspects of the Program is its ability to cater to the diverse needs and learning styles of its students. Whether a student is a visual learner, a kinesthetic learner, or a combination of the two, the Program's flexible and adaptable approach ensures that each individual's needs are met.Moreover, the Program's commitment to continuous innovation and improvement is truly commendable. The team of education experts and researchers behind the Program constantly analyze feedback, monitor student progress, and implement new strategies to enhance the learning experience.As a result, the Program has garnered widespread acclaim and recognition from both parents and industry experts. Numerous studies and testimonials have highlighted the remarkable progressand positive outcomes achieved by students enrolled in the Program.In conclusion, the "外研新思维英语少儿版go inside for lessons" is a pioneering initiative that redefines the landscape of language education. By creating an immersive, personalized, and collaborative learning environment, the Program empowers young English language learners to develop their linguistic skills while cultivating essential 21st-century competencies. As the world continues to evolve, programs like this one will undoubtedly play a crucial role in shaping the future of education and preparing our children for the challenges and opportunities that lie ahead.。
《新思维》、《新方法》对比简测《新思维》、《新方法》以及《大视野》都是黄东坡老师的著作,作为初中数学拔高类的教辅,一直以来都被老师、家长和学生所推崇。
其中《大视野》因为主要是涉及竞赛内容,在此我们不再赘述,《新思维》和《新方法》则是一直被认为是初中数学拔高类教辅中的佼佼者,有不少名校培优班的数学老师会选择两者之一作为补充练习。
普遍认为,《新思维》偏课内一些,《新方法》偏竞赛一些,难度更高。
但是到底《新思维》与《新方法》有什么区别,我们说《新方法》偏竞赛,到底有多“偏”?我们说《新方法》比《新思维》难,到底难到什么程度?想必朋友们市很好奇这件事情的,正好前一段朋友们打赏我的文章,我用这些钱又购置了一些教辅,其中就有七年级的《新方法》,正好可以和我手头的七年级《新思维》做一个简单的对比评测,为朋友选择教辅提供参考。
关于《新思维》的评测,我在之前已经写过。
见书识人——黄东坡《数学探究应用新思维(七年级数学)》评测所有这里我着重比较两者的区别,更侧重对新方法的分析。
目录一、《新思维》与《新方法》的结构对比二、《新思维》与《新方法》的题目结构与难度对比(一)、知识简析(二)、例题对比(三)、习题对比三、《新思维》与《新方法》到底怎么选?怎么用?(一)、怎么选?(二)、怎么用?四、小结一、《新思维》与《新方法》的结构对比两本书拿到手里,厚薄差不多,《新方法》略厚一些,去掉答案,《新方法》多了大概十几页。
两本书的体例都比较类似,大体都是以七年级数学教材为纲,但是又按照代数、几何、概率统计分别整合成几大块。
不过《新方法》又额外多了一部分拓展内容,这是它与《新思维》的区别。
我将两本书在各部分中的内容对照表整理出来,大家一看便知。
显然可以看出,在代数部分,《新方法》在内容上是包含了《新思维》的内容的,相较于《新思维》,《新方法》多了一些数学思维的拓展——走进美妙的数学世界、跨越——从算术到代数、创造的基石——观察、归纳与猜想;在一些知识上做了细化,比如一元一次方程中专门设置了绝对值与一元一次方程一节;增添了整式的乘法与除法、乘法公式等章节。
新思维英语朗文
《朗文新思维英语教程》是2006年由世界图书出版公司出版的一本英语教材,作者为Beatty。
该教程具有以下特色:
- 共分4个级别,难度分别与四级、六级、托福、考研等相当,既适用于读者自学又适用于教师课堂教学。
- 选材广泛,题材多样,涉及戏剧、诗歌、演讲、故事等,贴近学生的现实生活与兴趣爱好。
- 每单元分为两课,每课主题相同但观点各异。
基于该主题的辩论有利于学生加强交际能力。
- 精心设计阅读策略、测试技能、语言注释、文化点滴、课后练习等栏目,兼顾听力、口语与写作,提供完整的英语学习体系。
- 测试光盘体系健全,可生成适合教程各级别的试题库或进行在线测评,并可升级更新。
- 配有学习网站,提供更多视频/音频信息学习指导、在线交流及相关链接。
该教程包括学生用书(1~4)、教师用书(1~4)、录音CD或磁带(1~4)和测试光盘(CD-ROM Test Bank)等组件。
电磁感应现象中的能量问题
【重点知识梳理】
1、电磁感应现象
2、感应电流的产生条件
3、法拉弟电磁感应定律内容及公式,感生电动势和动生电动势
4、楞次定律的内容及应用,右手定则
5、互感现象、自感现象和涡流,自感系数的决定因素及单位
6、正弦交变电流的产生及函数表达式
7、交变电流的周期和频率、峰值和有效值
8、电感和电容对交变电流的影响
9、变压器原理、电压与匝数的关系,互感器
10、电能的输送的功率损失和电压损失
如图所示,电动机牵引一根原来静止的、长L为1m、质量m为0.1kg的导体棒MN
(1
(2
P
出
(2
,
电值
题型二:交变电流有效值综合问题
[例2]如图所示,ab =25cm ,ad =20cm ,匝数为50匝的矩形线圈.线圈总电阻 r =1Ω 外电路电阻R =9Ω,磁感应强度B =0.4T ,线圈绕垂直于磁感线的OO ’ 轴以角速度50rad/s 匀速转动.求:
(1)从此位置开始计时,它的感应电动势的瞬时值表达式. (2)1min 内R 上消耗的电能.
(3)当从该位置转过0
30时,通过R 上瞬时电功率是多少? (4)线圈由如图位置转过0
30的过程中,R 的电量为多少?
[解析](1)感应电动势的瞬时值表达式为t t S nB e 50cos 50cos ==ωω(V ) (2)电动势有效值为V E 225=,电流A r
R E
I 25.2=+=
1min 内R 上消耗的电能为J Rt I W 67502
==
(3
(4) ab R (1)(2)(3)
k (1[t
t E ∆∆00
当Δt→0时,02kvdt E =,安培力0
22r t d k F =。
(2)由Bld F =,得Bd F I =,回路消耗电能的功率为0
0222
2r vt d k R I P ==。
[变式训练3]如图所示,两根平行金属导轨固定在水平桌面上,每根导轨每米的电阻为
0.1Ω。
导轨的端点P 、Q 用电阻可忽略的导线相连,两导轨间的距离为0.2m 。
有随时间变化的匀强磁场垂直于桌面,已知磁感应强度B 与时间t 的关系为B=0.02t 。
一电阻不计的金属杆可在导轨上无摩擦地滑动,在滑动过程中保持与导轨垂直,在t=0时刻,金属杆紧靠在P 、Q 端,
在外力作用下,杆以恒定的加速度从静止开始向导轨的另一端滑动,求在t=0.6s 时金属杆所受的安培力。
,求用
(2 (1? (2上损耗的功率多大?
P
Q
【能力训练】
1.如图所示,用粗细相同的铜丝做成边长分别为L和2L的两只闭
合线框a和b,以相同的速度从磁感应强度为B的匀强磁场区域
中匀速地拉到磁场外,不考虑线框的动能,若外力对环做的功分
别为W a∶W b,则W a∶W b为()
A.1∶4 B.1∶2 C.1∶1 D.不能确定
2.超导磁悬浮列车是利用超导体的抗磁作用使列车车体向上浮起,同时通过周期性地变换磁极方向而获得推进动力的新型交通工具.其推进原理可以简化为如图所示的模型:在水平面上相距L的两根平行直导轨间,有竖直方向等距离分布的匀强磁场B1和B2,且B1=B2=B,每个磁场的宽都是l,相间排列,所有这些磁场都以速度v向右匀速运动.这时跨在两导轨间的长为L宽为l的金属框abcd(悬浮在导轨上方)在磁场力作用下也将会向右运动.设金属框的总电阻为R,运动中所受到的阻力恒为f,则金属框的最大速度可表示为()
A.v m= (B2L2v-fR)/B2L2B.v m= (2B2L2v-fR)/2B2L2
C.v m= (4B2L2v-fR)/4B2L2D.v m= (2B2L2v+fR)/2B2L2
3.如图甲所示边长为10 cm 的正方形金属线框
处在磁感应强度B=1. 0T 的有界匀强磁场
中,bc边平行于磁场边界,现用外力将线框
向右匀速拉出磁场,已知在线框拉出磁场区域
的过程中,ab 边受到的磁场力 F 随时间t
变化的关系如图乙所示,以bc边恰好离开磁
场的时刻为计时起点(即此时t= 0 )
求:( l )将金属框拉出的过程中线框产生的热
量Q .
( 2 )线框的电阻R.
4.如图所示,I、III为两匀强磁场区,I区域的磁场方向垂直纸
面向里,III区域的磁场方向垂直纸面向外,磁感强度均为B,
两区域中间为宽S的无磁场区II,有边长为L(L>S),电阻为
R的正方形金属框abcd置于I区域,ab边与磁场边界平行,
现拉着金属框以速度v向右匀速移动.试求:
(1)当ab边刚进入中央无磁场区II时,通过ab的电流的大
小和方向;
(2)当ab边刚进入磁场区III时,通过ab的电流的大小和方向;
(3)把金属框从I区域(图示位置)完全拉入III区域过程中拉力所做的功.
5.如图所示,边长L=2.5m、质量m=0.50kg的正方形金属线框,放在磁感应强度B=0.80T 的匀强磁场中,它的一边与磁场的边界MN重合.在力F作用下由静止开始向左运动,在5.0s内从磁场中拉出.测得金属线框中的电流随时间变化的图象如下图所示.已知金属线框的总电阻R=4.0Ω.
(1)试判断金属线框从磁场中拉出的过程中,线框中的感应电流方向,并在图中标出.(2)t=2.0s时金属线框的速度和力F的大小.
(3)已知在5.0s内力F做功1.92J,那么金属线框从磁场拉出的过程中,线框中产生的焦
耳热是多少?
6
7方
(2)为保持线圈匀速运动,需要多大外力?机械功率是多少?
8.如图所示,间距为L的光滑平行金属导轨,水平放置在竖直向下的磁感应强度为B的匀强磁场中,一端接阻值为R的电阻,一电阻为r、质量为m的导体棒放置在导轨上,在外力F的作用下从t=0时刻开始运动,其速度随时间变化规律是v=v m sinωt,不计电动轨电阻,求:
(1)从t=0到t=2π/ω时间内电阻R上产生的热量;
(2) 从t=0到t=π/2ω时间内外力F所做的功.
9.一小型水力发电站,水流量为2m3/s,落差为5m,发电机的总效率为50%,输出电压为240V,输电线总电阻为30Ω,为了使输电线损耗功率为发电机输出功率的6%,需要安装升压变压器,用户需要电压为220V,所以到用户需要装降压变压器,试求:
(1)升压变压器的原副线圈的匝数之比
(2)降压变压器原副线圈匝数之比
(3)能使多少盏“220V,110W”的电灯正常发光
参考答案:(电磁能量问题)
变式训练1 v =4.5m/s 、2R =6.0Ω 变式训练2 (1)R
n
r B Q 8424π=
(2)R
Br q 22
π=
(3)R
nB
r I 222π=
变式训练3 1.44X10-3
N
变式训练4 (1)131V ,14881W (2)12.5W
能力训练
1、A
2、C
3、(1) Q=2.0×10-
3J (2)因Q=I 2Rt, 所以R=Q/I 2t =1.0Ω
4、
(2(35、(2(36、7、8、9。