Nice setup! The real question is whether the magnetic field is due to the rate of change of the electric field between the plates (does that really produce a magnetic field in the space due to the changing electric field) or is what is measured simply from movement of charge (AC current) in the wires. It is difficult to separate the two in that experiment since the wires leading to the capacitor form a loop that will produce a magnetic field.
I like the theory of Ivor Catt: there is no displacement current, only a reflecting wave resulting in cancelling B and additive E, showing a steady Voltage and a hidden B in the cap.
According to Rosser, and to French the displacement current does not 'produce' any magnetic field. The integration that considers the fringe field will give zero contribute to B. The field inside the plates is due to the current elements in the wires only.
Great experiment! I am very new to this and I may sound really dumb but isn’t there an electric field between the plates? Is that displacement current? Does the changing electric field when ac is applied induce a magnetic field between the 2 plates?
Excellent experiment. But could the current in coil be due to changing magnetic field between the places during charging and discharging. Some say the magnetic field is due to changing electric field as charges progressively build up. Kindly clarify. Thanks
The coil is a magnetic field measuring device. It detects circulation of magnetic field, which doesn't necessarily have to be changing with respect to time. In the maths, circulation of magnetic field is proportional to both conduction current and time change of electric field.
Egregio Professore, come si nota dal minuto 1:15 al minuto 1:21 il campo magnetico ha la stessa intensità sia sul cavo rosso che sul cavo nero questo e corretto, tuttavia quando fa l'esperimento con il condensatore si nota un asimmetria , il campo magnetico prodotto dal cavo rosso è maggiore di quello prodotto dal cavo nero, da ciò si deduce che ci siano errori dovuti alle capacità parassite , probabilmente una parte del campo elettrico si chiude in qualcosa presente nel suo laboratorio, ciò si può notare al minuto 1:43 cavo nero ed 1:45 cavo rosso, mentre si nota il debole campo magnetico della presunta corrente di spostamento al minuto 1;44. purtroppo la questione del campo magnetico prodotto dalla corrente di spostamento non ha trovato ancora una soluzione. Si noti che al minuto 1:41 il toroide non si trova perfettamente parallelo alle piastre del condensatore e per tale motivo non si sta misurando un eventuale campo magnetico ma bensì un campo elettrico. Comunque Grazie per l'Esperimento. Wladimiro. Dear Professor, as you can see from minute 1:15 to minute 1:21 the magnetic field has the same intensity both on the red cable and on the black cable this is correct, however when you do the experiment with the capacitor you notice an asymmetry, the magnetic field produced by the red cable is greater than that produced by the black cable, from this we deduce that there are errors due to parasitic capacities, probably a part of the electric field closes in something present in his laboratory, this can be seen at 1 minute : 43 black cable and 1:45 red cable, while we note the weak magnetic field of the presumed displacement current at minute 1; 44. unfortunately the question of the magnetic field produced by the displacement current has not yet found a solution. Note that at minute 1:41 the toroid is not perfectly parallel to the plates of the capacitor and for this reason we are not measuring a possible magnetic field but an electric field. Anyway Thanks for the Experiment. Wladimir.
The Rogowski coil is primarily just copper wrapped in a spiral toroid. Ours also has a passive integrator to smooth out the signal and calculate the current. It is held together with a wooden frame and zip ties. There are tradeoffs with wire gauge--the larger gauge has lower resistivity and behaves more ideally, but it is much heavier. Smaller gauge can also allow for more wrappings. In general, you could account for the resistivity by approximating the overall resistance of the coil. There are enough variables involved in construction that calculating the behavior of the coil is going to be difficult if it's not made very precisely; however, if you don't mind calibrating it by testing it with known current sources, it will be much easier.
Perfect, now Maxwell-Ampere's law makes sense,throughout lot of text I see a experiment now,thanks you
Nice setup! The real question is whether the magnetic field is due to the rate of change of the electric field between the plates (does that really produce a magnetic field in the space due to the changing electric field) or is what is measured simply from movement of charge (AC current) in the wires. It is difficult to separate the two in that experiment since the wires leading to the capacitor form a loop that will produce a magnetic field.
I like the theory of Ivor Catt: there is no displacement current, only a reflecting wave resulting in cancelling B and additive E, showing a steady Voltage and a hidden B in the cap.
According to Rosser, and to French the displacement current does not 'produce' any magnetic field. The integration that considers the fringe field will give zero contribute to B. The field inside the plates is due to the current elements in the wires only.
Great effort
great demonstration
So this converts voltage to amperage. the amperage of the source doesn't matter? Since charging a capacitor is a function of the volrage
nice equipment, hope to see how DC does too during the moment of charging
Great experiment! I am very new to this and I may sound really dumb but isn’t there an electric field between the plates? Is that displacement current? Does the changing electric field when ac is applied induce a magnetic field between the 2 plates?
It seems to me that the magnetism does not come from the electricity itself but instead from the energy which passed trough the capacitor plates
Thx man this really helped me
Excellent experiment.
But could the current in coil be due to changing magnetic field between the places during charging and discharging. Some say the magnetic field is due to changing electric field as charges progressively build up. Kindly clarify.
Thanks
The coil is a magnetic field measuring device. It detects circulation of magnetic field, which doesn't necessarily have to be changing with respect to time. In the maths, circulation of magnetic field is proportional to both conduction current and time change of electric field.
What was the amplitude and frequency of the potential difference between the plates, please?
Egregio Professore, come si nota dal minuto 1:15 al minuto 1:21 il campo magnetico ha la stessa intensità sia sul cavo rosso che sul cavo nero questo e corretto, tuttavia quando fa l'esperimento con il condensatore si nota un asimmetria , il campo magnetico prodotto dal cavo rosso è maggiore di quello prodotto dal cavo nero, da ciò si deduce che ci siano errori dovuti alle capacità parassite , probabilmente una parte del campo elettrico si chiude in qualcosa presente nel suo laboratorio, ciò si può notare al minuto 1:43 cavo nero ed 1:45 cavo rosso, mentre si nota il debole campo magnetico della presunta corrente di spostamento al minuto 1;44. purtroppo la questione del campo magnetico prodotto dalla corrente di spostamento non ha trovato ancora una soluzione. Si noti che al minuto 1:41 il toroide non si trova perfettamente parallelo alle piastre del condensatore e per tale motivo non si sta misurando un eventuale campo magnetico ma bensì un campo elettrico. Comunque Grazie per l'Esperimento. Wladimiro.
Dear Professor, as you can see from minute 1:15 to minute 1:21 the magnetic field has the same intensity both on the red cable and on the black cable this is correct, however when you do the experiment with the capacitor you notice an asymmetry, the magnetic field produced by the red cable is greater than that produced by the black cable, from this we deduce that there are errors due to parasitic capacities, probably a part of the electric field closes in something present in his laboratory, this can be seen at 1 minute : 43 black cable and 1:45 red cable, while we note the weak magnetic field of the presumed displacement current at minute 1; 44. unfortunately the question of the magnetic field produced by the displacement current has not yet found a solution. Note that at minute 1:41 the toroid is not perfectly parallel to the plates of the capacitor and for this reason we are not measuring a possible magnetic field but an electric field. Anyway Thanks for the Experiment. Wladimir.
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Could someone please explain why the current graph does not reach zero when the coil is taken out of the circuit?
Agreed also the graph changes a lot when we go from between te capacitor plates to the sides although there should be no change
Thanks man
Good sense
Which university is he teaching
Hi, what materials would be needed to recreate this demo? Also does the wire gauge within the torus affect the current?
The Rogowski coil is primarily just copper wrapped in a spiral toroid. Ours also has a passive integrator to smooth out the signal and calculate the current. It is held together with a wooden frame and zip ties. There are tradeoffs with wire gauge--the larger gauge has lower resistivity and behaves more ideally, but it is much heavier. Smaller gauge can also allow for more wrappings. In general, you could account for the resistivity by approximating the overall resistance of the coil. There are enough variables involved in construction that calculating the behavior of the coil is going to be difficult if it's not made very precisely; however, if you don't mind calibrating it by testing it with known current sources, it will be much easier.
Cool 😎🤠
Ok
Experiment with a lot error
Anyway thanks for setup
Maxwell 4 equation time varying magnetic field