Whether the DC power supply has excess charge itself or not, if it can apply the desired voltage difference between the electrodes (which you can check with a voltmeter), then the expected surface charges (one net positive, the other net negative) will be there at the facing surfaces, in accordance with Gauss's law, see: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/gaulaw.html http://hyperphysics.phy-astr.gsu.edu/hbase/electric/elesht.html#c2
Michel ----- Original Message ----- From: "Horace Heffner" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Monday, August 13, 2007 7:32 PM Subject: Re: [Vo]:Re: Only potential differences matter > > On Aug 13, 2007, at 7:44 AM, Michel Jullian wrote: > >>> >>> 1. Is it possible to establish a condition where it is certain there >>> are more negative charges than positive at some point P on a given >>> plate surface? >>> >>> 2. Is it possible to establish a condition where it is certain there >>> are more positive charges than negative at some point P on a given >>> plate surface? >>> >>> I think it is possible to do both. >> >> Of course it is possible! For 1 connect the plate to the most >> negative pole of a DC power supply, and connect a counterelectrode, >> e.g. a ball held close to point P, to the most positive pole. For 2 >> reverse the polarities. > > Suppose the DC power supply, a battery, carries a coulomb of excess > positive charge, or a coulomb of excess negative charge? > > Horace Heffner > http://www.mtaonline.net/~hheffner/ > > >
