第7讲:电容,场能Lecture 7: Capacitance, Field Energy |
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课程网址: | http://videolectures.net/mit802s02_lewin_lec07/ |
主讲教师: | Walter H. G. Lewin |
开课单位: | 麻省理工学院 |
开课时间: | 2008-10-10 |
课程语种: | 英语 |
中文简介: | //“......组装费用,我必须做的工作,我们之前讨论过。我们称之为静电势能。今天,我将以不同的方式看待这个能量概念,我会用能量来评估能量假设我有两个平行板,我用正电荷充电,这是表面电荷密度乘以板的面积,这一个,负电荷,这是表面电荷密度负电荷的倍数我们假设这两者之间的分离是H,所以我们有一个近似恒定的电场,这里的电场是sigma除以epsilon // //现在,我我要去上盘,我要把它向上移动。所以当我这样做时,我必须施加一个力,因为这两个板块相互吸引,所以我必须做好工作。我把它移动起来,我将它移动到距离X上,我在这里创造,电场以前不存在......“/ / |
课程简介: | //"...assemble charges, I have to do work, we discussed that earlier. And we call that electrostatic potential energy. Today, I will look at this energy concept in a different way, and I will evaluate the energy in terms of the electric field. Suppose I have two parallel plates, and I charge this one with positive charge, which is the surface charge density times the area of the plate, and this one, negative charge, which is the surface charge density negative times the area of the plate. And let's assume that the separation between these two is H, and so we have an electric field, which is approximately constant, and the electric field here is sigma divided by epsilon zero.// //And now, I'm going to take the upper plate, and I'm going to move it up. And so as I do that, I have to apply a force, because these two plates attract each other, so I have to do work. And as I move this up, and I will move it up over distance X, I am creating here, electric field that wasn't there before...."// |
关 键 词: | 电场; 电容; 场能 |
课程来源: | 视频讲座网 |
最后编审: | 2019-05-23:yuh |
阅读次数: | 37 |