Physics Help Forum Energy stored in magnetic field

 Electricity and Magnetism Electricity and Magnetism Physics Help Forum

Jan 19th 2015, 11:39 AM   #11
Junior Member

Join Date: Oct 2014
Posts: 13
 Originally Posted by Farsight That video is wrong, and it's repeating a popscience myth. A charged particle goes around the concentric "magnetic field lines" around the current-in-the-wire.
There doesn't seem to be anything wrong with the video. I suspect that the real problem that you have is that the physics presented here doesn't match the peculiar version of physics that you have in your self-published book.

 Jan 19th 2015, 12:30 PM #12 Senior Member   Join Date: May 2014 Location: Poole, UK Posts: 132 No, it doesn't match what Minkowski said. Or what Maxwell said: "a motion of translation along an axis cannot produce a rotation about that axis unless it meets with some special mechanism, like that of a screw". Or what actually happens to particles in a magnetic field. Or bog-standard electromagnetism wherein "the curl operator on one side of these equations results in first-order spatial derivatives of the wave solution, while the time-derivative on the other side of the equations, which gives the other field, is first order in time". People tend not to appreciate this spatial and time-derivative stuff. For an analogy, imagine you're in a canoe on a flat calm ocean, and then this big troughless hump of water comes at you. This represents electromagnetic four-potential, see the bottom half of the picture below. The degree of slope of your canoe denotes E, and the rate of change of slope denotes B. At the top of the hump, your canoe is flat and momentarily still. That's where the sinusoidal electromagnetic wave is at zero. The sinusoidal electric wave maps out the slope of your canoe, the sinusoidal magnetic wave maps out the rate of change of slope of your canoe. But there aren't really two different waves. They're just two aspects of the electromagnetic wave. Attached Thumbnails   Last edited by Farsight; Jan 19th 2015 at 12:34 PM.
 Jan 19th 2015, 12:42 PM #13 Junior Member   Join Date: Oct 2014 Posts: 13 You are demanding of the video something that it does not have to do. It's doing a fine job of presenting the basics of the physics involved. The only "problem" you have is that the video doesn't explicitly refer to specific features of electromagnetism as a relativistic theory and that it doesn't explore your favorite quotations from the past. Please make your own video that as simply, and accurately, presents the topic along with the relativistic discussion. Edit: you now appear to have added some mathematically suspect stuff. This is a help forumk could you please produce the mathematics to support your claims about derivatives above?
 Jan 19th 2015, 03:48 PM #14 Forum Admin     Join Date: Apr 2008 Location: On the dance floor, baby! Posts: 2,811 I have to admit that I haven't taken a look-see at the energy storage problem. There is nothing wrong with the video. And this conversation has gone way beyond the OPs question, who hasn't apparently even visited the thread since August. If you would like to discuss this more then please start a new thread, -Dan __________________ Do not meddle in the affairs of dragons for you are crunchy and taste good with ketchup. See the forum rules here.

 Tags energy, field, magnetic, stored

 Thread Tools Display Modes Linear Mode

 Similar Physics Forum Discussions Thread Thread Starter Forum Replies Last Post romakarol Electricity and Magnetism 1 Feb 25th 2016 06:18 AM thespardian Energy and Work 4 May 6th 2014 11:35 AM theramblingmark Electricity and Magnetism 1 Jan 15th 2010 08:03 PM Susaluda Advanced Electricity and Magnetism 1 May 25th 2009 12:12 AM