poynt99, Your analysis is correct but I think you may wish to dig a bit deeper into the physics. Lewin is famous for dropping bombs to make you think The big problem with determining if the good prof is wrong is you must take a stand on whether magnetic fields are truly conservative, in this sense. By that, I mean conservative in equal distribution of energy on all points of the loop. Since one side has a resistor 9x the other side, are both sides producing the same amount of waste heat? If they aren't then both sides are not equal in the initial eddy current or the current due to Ampere/Turns. I'm not disagreeing with your ideas. There are some unknowns about his experiment causing me to wonder if he really did provide a true example of a non-conservative field. Conservative fields store energy without loss. The net work done by a non-conservative field taken around a closed loop is non-zero. The net work is invariably negative. Or, a non-conservative field dissipates energy. Magnetic fields cannot gain or loose energy. Magnetic fields, or magnetic flux density in motion, will actually change motion (direction, density, etc.) because this is true. So, what I'm wondering is this a special case where the uneven loss of energy from the uneven resistances is cause for also uneven eddy currents & CEMF? If so, the minor inductance you show on your circuit may be the means for the separation between the loop sides and Lewin made use of those. There doesn't seem to be any close-ups of the exact setup. So, saying he is wrong or right are only words, unless you are convinced there is no true example of non-conservative induction. In any case, those other professors mentioned don't deserve an apology. They should have corrected Lewin or agreed with his experiment. They did neither.
« Last Edit: 2011-02-21, 10:55:42 by WaveWatcher »
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