Return-Path: Received: (qmail 10532 invoked from network); 8 Nov 2002 13:37:04 -0000 Content-Transfer-Encoding: 8bit Received: from marstons.services.quay.plus.net (212.159.14.223) by mailstore with SMTP; 8 Nov 2002 13:37:04 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: (qmail 2978 invoked by uid 10001); 8 Nov 2002 12:36:24 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from post.thorcom.com (193.82.116.70) by marstons.services.quay.plus.net with SMTP; 8 Nov 2002 12:36:24 -0000 Received: from majordom by post.thorcom.com with local (Exim 4.10) id 18A8MH-0003r8-00 for rsgb_lf_group-outgoing@blacksheep.org; Fri, 08 Nov 2002 12:35:33 +0000 Received: from [212.164.44.2] (helo=astral.omskcity.com) by post.thorcom.com with esmtp (Exim 4.10) id 18A8MG-0003qz-00 for rsgb_lf_group@blacksheep.org; Fri, 08 Nov 2002 12:35:32 +0000 Received: from fitec.omskcity.com (mu03.dialup1.infomsk.ru [212.164.45.195]) by astral.omskcity.com (8.9.3/8.9.3) with SMTP id SAA3dcbaeee3a0e for ; Fri, 8 Nov 2002 18:32:46 +0600 (OS) Date: Fri, 8 Nov 2002 18:32:24 +0000 (GMT) From: "Alexander S. Yurkov" To: rsgb_lf_group@blacksheep.org In-reply-to: <5.1.0.14.0.20021108112020.00aeef28@gemini.herts.ac.uk> Message-ID: MIME-Version: 1.0 Subject: Re: LF: To Ponder over the weekend Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Spam-Status: No, hits=-1.6 required=5.0tests=DATE_IN_FUTURE_03_06,EMAIL_ATTRIBUTION,IN_REP_TO, QUOTED_EMAIL_TEXT,SPAM_PHRASE_00_01,USER_AGENT_PINEversion=2.42 Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group On Fri, 8 Nov 2002, James Moritz wrote: > Here is another conundrum along similar lines - you have two identical, > loss-free 1uF capacitors, one is charged to 10V, the other is discharged. > You then connect the two in parallel so the total C is now 2uF - charge > will flow from the charged capacitor into the discharged capacitor. > Assuming charge Q is conserved, and that Q=CV, the voltage must now be 5V. > But the stored energy in a capacitor =1/2CV^2, so with the single charged > capacitor, the stored energy is 1/2 x 1u x 100 = 50uJ, while with both > capacitors in parallel it is only 1/2 x 2u x 25 = 25uJ. So where has the > other 25uJ gone? It is radiated or converted to heat. If there is no any losses (ideal case) 25uJ is energe of magnetic field (there should be continously oscilation if there is no disipation...) But I do not think this is analogy to drained oil... 73 de RA9MB/Alex http://www.qsl.net/ra9mb