P33 1-21一台并励直流发电机P=16kW,Ux=230V,IN=6.6A,n1600r/min电枢回路电阻 R=0.1282,励磁回路电阻R=150Q,额定效率n=85.5%试求额定工作状态下的励磁电 流、电枢电流、电枢电动势、电枢铜耗、输入功率、电磁功率

To improve practical skills on listening& speaking

I. Introductory Remarks Why do nations trade? They trade for many reasons. First, they trade because there are differences in natural resources in different parts of the world. The second reason is that pays to specialize, for specialization enables one country to produce some goods more cheaply than another country and brings benefits as one country shares their cheap goods with

Unit Two Text B 1. Pre-reading Ta 1. How did the first american music begin? Why do so many people around world love American music? 3. What role does modern science play in the development of American music? 4. When and where did the word \music!\first appear in the American history?

To improve practical skills on listening& speaking

Unit Two Text A Unit Two Text A l. Pre-reading Task ll. Related Information lll. Detailed Study lV. Outline& Summary V. Home Assignment

To improve practical skills on listening& speaking

New Experience FR Hf To study Text A in detail (that is, to get to know the uses of some key words and phrases andto know more about college life

概述 GPS是英文 Navigation Satellite Timing and Ranging G| obal Positioning System的缩写,意为利用卫星导航进行 测时和测距,以构成全球卫星定位系统。是美国国防部主要 为满足军事部门对海上、陆地和空中设施进行髙精度导航 和定位的需要而建立的。自1973年美国军方批准成立联合 计划局开始GPS的研究工作到1993年系统建成该工程历时 20年,耗资300亿美元,成为继阿波罗登月计划和航天飞 机计划之后的第三项庞大空间计划。它从根本上解决了人 类在地球上的导航和定位问题,在军事和工农业等领域得 到了广泛的应用。给导航和定位技术带来了巨大的变化

第1节电机的应用与分类 第2节本教材内容、课程性质、教学目的、学习方法 第3节电机中常用的基本定律 第4节电机中铁磁材料的特点