作者espreesso (教授为什麽没告诉我)
站内Electronics
标题Re: [问题]电容比例计算(P币1000)
时间Thu Jun 19 12:36:53 2008
※ 引述《kj66 (无聊的夏天)》之铭言：
: 一题习题不会算..想请会的板友帮忙一下,
: 感谢(给1000P币,我所有财产了= =)
: Consider two capacitors with top plates as shwon
: http://tinyurl.com/665jfp
: Show that the perimeter/area ratio is the same in both,
: and determine the value of b required for a capacitance
: ratio η>1
for 正方形那个
p/a = 4a/a^2=4/a;
另一个
p/a=(4a+2b)/(a^2+ab/2)
= (4/a) ( (2a+b) / (2a+b) )
= 4/a;
故得证
for a capacitance ratio η>1
a^2+ab/2 = η a^2;
==> b=2a(η-1) #
--
※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 59.124.164.52
1F：→ espreesso:不过建议若要固定p/a ratio lay成长方形就好 06/19 12:39
2F：→ espreesso:请参阅martin的书 06/19 12:41
3F：推 kj66:非常感谢 06/19 14:09