Thanks to Harvey and ION for bringing this experiment to light (again). [ION, this was the "treat" I was going to offer the other day]. Video demonstration: Part 1 and Part 2We've discussed this experiment and concluded that Professor Lewin is incorrect in his assessment of his observations made regarding this experiment. The fields are indeed fully conserved, and it is more of a measurement error combined with an assumption which allowed him to come to this conclusion that the voltages measured are different depending on the direction taken. Well, this is true, but Lewin has incorrectly assumed that he is measuring the same exact points in the circuit for each resistor. He is not. I enjoy the challenge of being able to simulate various things using SPICE. This was no exception. I believe I have clearly shown that this experiment can be simulated, and that Professor Lewin was incorrect in his assessment. I also feel that Lewin may owe those other professors he talked about in his video-taped class regarding this experiment, an apology. They were correct in their disbelief, but they should have known why and where Lewin was in error. Lewin_NCF_01.png shows the circuit and the resulting voltage measurements. Each probe is positive at the top. L3 is the solenoid, and L1, L2 represent the wiring between the resistors, and comprise part of the induction loop. Clearly Lewin overlooked the fact that the wiring represents an inductance in the loop and in a dynamic sense, points A, A' and D, D' are not the same at all. This is why the voltage is measured to be quite different. Lewin must have had the scope probes set across each resistor as shown. Lewin_NCF_02.png illustrates the probe locations had he actually placed them across the exact center of the wiring, as he has "implied". Can anyone have a go at what the actual voltage measurement would have been, had he placed the probes in the center at position A and D (purple probes)?
Note that in this case, BOTH scope probes would have measured exactly the same voltage. I'll post the solution after you've all had a chance to contemplate it a little and offer your answers. .99
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"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa
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Topic: Professor Walter Lewin's Non-conservative Fields Experiment (Read 330016 times)
