X-Authentication-Warning: delorie.com: mail set sender to geda-user-bounces using -f X-Recipient: geda-user AT delorie DOT com Message-ID: <4F6354C2.10502@keensupport.net> Date: Fri, 16 Mar 2012 07:57:06 -0700 From: Joe Knapp Organization: Keen Support Services, LLC User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.2) Gecko/20120216 Thunderbird/10.0.2 MIME-Version: 1.0 To: geda-user AT delorie DOT com Subject: Re: [geda-user] Daughter's Science Fair References: <20120316142719 DOT 26210 DOT qmail AT stuge DOT se> <4F63506D DOT 90602 AT keensupport DOT net> In-Reply-To: <4F63506D.90602@keensupport.net> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Reply-To: geda-user AT delorie DOT com Rob, What may work for you though, is that if you place the two coils, perhaps in series, perhaps adjacent, one with the light bulb connected and the other with the battery, you may see the light bulb illuminate briefly when you disconnect the battery. This is due to the rapidly diminishing magnetic field produced by the coil connected to the C battery. I think that is enough random comments from me. Good Luck, Joe On 03/16/2012 07:38 AM, Joe Knapp wrote: > Sorry, missed the whole point about DC. Absolutely true. > > On 03/16/2012 07:27 AM, Peter Stuge wrote: >> Rob Butts wrote: >>> shouldn't the electromagnetic field produced by the coil and nail >>> with the battery induce a current in the other coil when placing >>> the nails adjacent and parallel? >> There are no DC transformers, right? >> >> http://van.physics.illinois.edu/qa/listing.php?id=2354 >> >> >> //Peter >> -- Keen Support Services, LLC http://keensupport.net