referencing this: https://www.allaboutcircuits.com/textbook/alternating-current/chpt-3/ac-inductor-circuits/
At the beginning of the current through the inductor, the opposition to the current (positive voltage) is at it's peak - I get that. But if there is opposition, then not as much current would flow, invalidating the assumption about the amount of changing current in the beginning? I mean how can changing current induce opposition that would prevent the current from changing in the first place?
Another thing that is confusing is that when reading about inductors, they always talk about that 90° phase shift between current and voltage. But that 90° shift pertains only to the voltage/current across the inductor, induced by the inductor, not the whole circuit at hand, right? After all, I can't just take a circuit's wire, wind it around my screwdriver a couple times and suddenly the current curve of the whole circuit lags the voltage curve by 90°?
Intuitively, and with the help of circuitlab.com, I come to the conclusion that inserting a very small inductor into the circuit would not be noticeable at first. Gradually increasing the inductor in size will slowly create a lagging current curve in the circuit, while also gradually attenuating the signal, i.e. less current overall / smaller current amplitude. By the time that the inductor is so large to induce a current lag of 90° in the whole circuit, it would be so large that practically no current would flow?
Every resource I consult keeps repeating the same paradigms over and over like "the inductor wants to keep current flowing" but that does not really help me much. I wonder if I just don't get it. How would I go about plotting a circuit's voltage and current curve, knowing that the voltage that can be dropped by the inductor at di/dt times henrys equals such and such volts?
At the beginning of the current through the inductor, the opposition to the current (positive voltage) is at it's peak - I get that. But if there is opposition, then not as much current would flow, invalidating the assumption about the amount of changing current in the beginning? I mean how can changing current induce opposition that would prevent the current from changing in the first place?
Another thing that is confusing is that when reading about inductors, they always talk about that 90° phase shift between current and voltage. But that 90° shift pertains only to the voltage/current across the inductor, induced by the inductor, not the whole circuit at hand, right? After all, I can't just take a circuit's wire, wind it around my screwdriver a couple times and suddenly the current curve of the whole circuit lags the voltage curve by 90°?
Intuitively, and with the help of circuitlab.com, I come to the conclusion that inserting a very small inductor into the circuit would not be noticeable at first. Gradually increasing the inductor in size will slowly create a lagging current curve in the circuit, while also gradually attenuating the signal, i.e. less current overall / smaller current amplitude. By the time that the inductor is so large to induce a current lag of 90° in the whole circuit, it would be so large that practically no current would flow?
Every resource I consult keeps repeating the same paradigms over and over like "the inductor wants to keep current flowing" but that does not really help me much. I wonder if I just don't get it. How would I go about plotting a circuit's voltage and current curve, knowing that the voltage that can be dropped by the inductor at di/dt times henrys equals such and such volts?
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