作者espreesso (教授為什麼沒告訴我)
站內Electronics
標題Re: [問題]電容比例計算(P幣1000)
時間Thu Jun 19 12:36:53 2008
※ 引述《kj66 (無聊的夏天)》之銘言:
: 一題習題不會算..想請會的板友幫忙一下,
: 感謝(給1000P幣,我所有財產了= =)
: 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 正方形那個
p/a = 4a/a^2=4/a;
另一個
p/a=(4a+2b)/(a^2+ab/2)
= (4/a) ( (2a+b) / (2a+b) )
= 4/a;
故得証
for a capacitance ratio η>1
a^2+ab/2 = η a^2;
==> b=2a(η-1) #
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◆ From: 59.124.164.52
1F:→ espreesso:不過建議若要固定p/a ratio lay成長方形就好 06/19 12:39
2F:→ espreesso:請參閱martin的書 06/19 12:41
3F:推 kj66:非常感謝 06/19 14:09