- #246
yungman
- 5,755
- 293
I keep thinking about the measuring method and about the path dependent. My problem with all the argument is this:
Just because we have not yet found a way to do measurement without getting the loop induced emf onto the probe do not mean the is not a potential different between point B and D, or point C and D. We are stipulating that we don't measure the emf because of the probes' ground lead. But let say for a second that We come up with a way to break the loop on the probe so we avoid the induced emf onto the probe, we should actually see the potential difference between point D and C like what Sarumonkee. So the issue is not that KVL don't work here, the issue is we have to find a way to get rid of the measuring instrument induced error. If we can succeed in getting rid of the measurment error, we can apply KVL on this closed loop with resistors.
There got to be a way to do accurate measurement and we should see the induced emf on the wire. I am trying to come up with a way to do the measurement, so far no luck yet.
I attached a priminary schematic drawing of a circuit to measure the voltage between point B and D of the loop. I use two section of preamp that use isolated supply and produce a differential output. The two pair of differential output is then sum together. I use differential outputs because any induced emf will become common mode and rejected by the differential amp in the following stage. As I said, this is priminary, but there got to be a way to get rid of the error of measurement. Our think about this more tomorrow.
Just because we have not yet found a way to do measurement without getting the loop induced emf onto the probe do not mean the is not a potential different between point B and D, or point C and D. We are stipulating that we don't measure the emf because of the probes' ground lead. But let say for a second that We come up with a way to break the loop on the probe so we avoid the induced emf onto the probe, we should actually see the potential difference between point D and C like what Sarumonkee. So the issue is not that KVL don't work here, the issue is we have to find a way to get rid of the measuring instrument induced error. If we can succeed in getting rid of the measurment error, we can apply KVL on this closed loop with resistors.
There got to be a way to do accurate measurement and we should see the induced emf on the wire. I am trying to come up with a way to do the measurement, so far no luck yet.
I attached a priminary schematic drawing of a circuit to measure the voltage between point B and D of the loop. I use two section of preamp that use isolated supply and produce a differential output. The two pair of differential output is then sum together. I use differential outputs because any induced emf will become common mode and rejected by the differential amp in the following stage. As I said, this is priminary, but there got to be a way to get rid of the error of measurement. Our think about this more tomorrow.
Attachments
Last edited: