Professor Walter H G Lewin

	Professor Lewin, MIT
Dear Professor Walter H G Lewin, In your MIT lecture 18 at http://videolectures.net/mit802s02_lewin_lec18/ you drew lines showing electric current spreading out over the capacitor plate. That is, you mentioned that electric current flows across the capacitor plate, at right angles to the main flow. However, this was just in passing, and you did not discuss the magnetic field which must result in the horizontal direction, using Ampere's Law, or its effect on the use of Kirchhoff's First Law at the entry point into the capacitor - see Wikipedia; "At any point in an electrical circuit that does not represent a capacitor plate, the sum of currents flowing towards that point is equal to the sum of currents flowing away from that point.". This lateral flow of electric current had been overlooked for over a century, until I pointed it out in 1978 at http://www.ivorcatt.org/icrwiworld78dec1.htm . Please comment on the implications of this current as discussed by me in 1978. I also treat it at http://www.ivorcatt.com/411.htm In your lecture, you drew parallel lines indicating that the electric field in the capacitor is uniform. http://www.electromagnetism.demon.co.uk/3615.htm http://www.ivorcatt.org/icz014.htm . Please comment on my comments here. Ivor Catt.14 May 2009 21:05 @@@@@@@@@@@@ Reply within half an hour. ----- Original Message ----- From: "Walter H.G. Lewin" <lewin@space.mit.edu> To: <icatt@btinternet.com> Cc: <lewin@space.mit.edu> Sent: Thursday, May 14, 2009 9:25 PM Subject: Re: capacitor Kirchhoff's current rule does not apply for a given point on the capacitor plates. At one point in time charges can be flowing to a point and at another point in time charge can be flowing away from that point. Imagine you charge a capacitor plate with a DC power supply (a battery). Look at ONE plate of a parallel plate capacitor. This plate gets charged. Thus charge must have been flowing to the plate. I hope this helps. @@@@@@@@@ I'm afraid not. Ivor Catt. 14 May 2009 21.52 @@@@@@@@ 28 May 2009 Dear Professor Lewin, Thank you for your limited reply about Kirchhoff (at bottom of http://www.ivorcatt.co.uk/95.htm ). I have removed that minor part about Kirchhoff from my questions, and submit the rest to you now. Ivor Catt ----- Original Message ----- From: ivor catt To: lewin@mit.edu Cc: various Sent: Thursday, May 14, 2009 9:05 PM Subject: capacitor Dear Professor Walter H G Lewin, http://www.ivorcatt.co.uk/95.htm In your MIT lecture 18 at http://videolectures.net/mit802s02_lewin_lec18/ you drew lines showing electric current spreading out over the capacitor plate. That is, you mentioned that electric current flows across the capacitor plate, at right angles to the main flow. However, this was just in passing, and you did not discuss the magnetic field which must result in the horizontal direction, using Ampere's Law. This lateral flow of electric current had been overlooked for over a century, until I pointed it out in 1978 at http://www.ivorcatt.org/icrwiworld78dec1.htm . Please comment on the implications of this current as discussed by me in 1978. I also treat it at http://www.ivorcatt.com/411.htm In your lecture, you drew parallel lines indicating that the electric field in the capacitor is uniform. http://www.electromagnetism.demon.co.uk/3615.htm http://www.ivorcatt.org/icz014.htm . Please comment on my comments here. Ivor Catt @@@@@@@@@@@@@ Dear Professor Lewin, I look forward to your reply to my second email, dated 28 May 2009 Ivor Catt 9 June 2009 4 January 2010. Still no reply. But on the www it says that he replies to all his emails. His Wikipedia entry says; “Lewin personally responded to hundreds of e-mail requests that he received per year from UWTV viewers”. – Ivor Catt. @@@@@@@@@@@@@ Correspondence with Ian Montgomery, 1 July 2009, about Lewin's failure to reply to my second email
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