Return-Path: Received: (qmail 23320 invoked from network); 8 Nov 2002 12:35:23 -0000 Received: from marstons.services.quay.plus.net (212.159.14.223) by mailstore with SMTP; 8 Nov 2002 12:35:23 -0000 Received: (qmail 3862 invoked by uid 10001); 8 Nov 2002 12:37:29 -0000 Received: from post.thorcom.com (193.82.116.70) by marstons.services.quay.plus.net with SMTP; 8 Nov 2002 12:37:29 -0000 Received: from majordom by post.thorcom.com with local (Exim 4.10) id 18A8NS-0003sL-00 for rsgb_lf_group-outgoing@blacksheep.org; Fri, 08 Nov 2002 12:36:46 +0000 Received: from [130.244.199.132] (helo=fep04-svc.swip.net) by post.thorcom.com with esmtp (Exim 4.10) id 18A8NS-0003sB-00 for rsgb_lf_group@blacksheep.org; Fri, 08 Nov 2002 12:36:46 +0000 Received: from oemcomputer ([213.101.40.196]) by fep04-svc.swip.net with SMTP id <20021108123644.QXLC19257.fep04-svc.swip.net@oemcomputer> for ; Fri, 8 Nov 2002 13:36:44 +0100 Message-ID: <005201c28723$9fbd8cc0$c12565d5@oemcomputer> From: "Johan Bodin" To: rsgb_lf_group@blacksheep.org References: <7D653C9C42F5D411A27C00508BF8803DCB9CBB@mail.dstl.gov.uk> <000701c28713$e15270c0$0504210a@c.scope> Date: Fri, 8 Nov 2002 13:36:55 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2600.0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Subject: LF: Re: Re: To Ponder over the weekend Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, hits=-0.1 required=5.0tests=EMAIL_ATTRIBUTION,NO_COST,REFERENCES,SPAM_PHRASE_00_01, USER_AGENT_OEversion=2.42 Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group g6tmk wrote: > My guess is the 10uF capacitor becomes 1uF and the voltage rises to 100V. That's my guess too, but... W [stored energy] = V^2*C / 2: With oil: V=10V, C=10u => W = 10*10*10u / 2 = 500 uJ Without oil: V=100V, C=1u => W = 100*100*1u / 2 = 5000 uJ Assuming that no charge goes away with the oil, the stored energy will increase by a factor of ten. Hmm... Force * distance = energy. When gravity pulls the oil away from the plates, the oil has to fight against an electrostatic force thereby injecting energy into the capacitor, I guess... Will a charged air variable capacitor try to turn itself towards the maximum setting? :-) 73 Johan SM6LKM