Over the past 2 or 3 weeks I’ve been getting all tangled up in inductors,blimey , it’s like being forced to watch two different tennis matches simultaneously! Very confusing for a feeble scientific brain like mine. However, the mists are clearing and I think I’m beginning to get the hang of it at last.
As I am speaking now, I AM LOOKING AT A PICTURE OF ONE CYCLE OF A SINE WAVE, WHICH IS STUCK ON MY WALL, AND I AM IMAGINING THAT THIS SINE WAVE REPRESENTS THE SUPPLY CURRENT THAT IS GOING THROUGH AN INDUCTOR.
I understand that it is a changing magnetic field that causes a voltage to be induced in the inductor, a voltage which opposes the supply voltage. I understand now that this induced voltage is at its strongest when the current wave is on its steepest parts, because that is when the current/magnetic field is changing most rapidly.
WHAT I AM NOT TOO SURE ABOUT IS EXACTLY WHAT IS HAPPENING TO THE MAGNETIC FIELD AROUND THE INDUCTOR (& THUS ALSO OF COURSE THE INDUCED BACK-VOLTAGE) DURING EACH STAGE OF THE CORRESPONDING CURRENT SINE WAVE.
That is, on the steepest part of the leading edge (I think that’s the right expression)of the current sine wave, I suppose the INDUCED VOLTAGE will be rising.
But how about when the wave is falling from its 1st +ve peak, going down towards 0? What is happening to the magnetic field (and thus also, to the induced back-voltage) at this stage? I mean, does the induced magnetic field change its polarity or anything, when the current is falling?
And how about the part of the current sine wave where it cuts through the horizontal axis at 0, and changes direction? What happens to the magnetic field (and thus also to the induced back-voltage) at this point, when the current has changed direction, but is rising?
In short, I suppose I am a little confused because the relationship between SUPPLY CURRENT AND the magnetic field/induced voltage is tricky because it’s so complex:
SUMMARY OF WHAT I DON'T UNDERSTAND
AN INCREASED CHANGE IN ONE THING (current level/magnetic field) CAUSES A SIMPLE INCREASE IN ANOTHER (nduced voltage)
BUT WHAT DOES A SIMPLE INCREASE/DECREASE IN ONE THING (current level/magnetic field)CAUSE TO HAPPEN TO ANOTHER?(induced voltage)
AND WHAT DOES A CHANGE IN DIRECTION IN ONE THING (current/magnetic field) CAUSE TO HAPPEN TO ANOTHER? (induced voltage)
I’m sorry this is so long. If anyone could deal with any of my points at all, or perhaps point me in the right direction, I’d be very grateful. I may not completely understand any answers, it takes time with me, but hopefully I will progress a little more in understanding.
As I am speaking now, I AM LOOKING AT A PICTURE OF ONE CYCLE OF A SINE WAVE, WHICH IS STUCK ON MY WALL, AND I AM IMAGINING THAT THIS SINE WAVE REPRESENTS THE SUPPLY CURRENT THAT IS GOING THROUGH AN INDUCTOR.
I understand that it is a changing magnetic field that causes a voltage to be induced in the inductor, a voltage which opposes the supply voltage. I understand now that this induced voltage is at its strongest when the current wave is on its steepest parts, because that is when the current/magnetic field is changing most rapidly.
WHAT I AM NOT TOO SURE ABOUT IS EXACTLY WHAT IS HAPPENING TO THE MAGNETIC FIELD AROUND THE INDUCTOR (& THUS ALSO OF COURSE THE INDUCED BACK-VOLTAGE) DURING EACH STAGE OF THE CORRESPONDING CURRENT SINE WAVE.
That is, on the steepest part of the leading edge (I think that’s the right expression)of the current sine wave, I suppose the INDUCED VOLTAGE will be rising.
But how about when the wave is falling from its 1st +ve peak, going down towards 0? What is happening to the magnetic field (and thus also, to the induced back-voltage) at this stage? I mean, does the induced magnetic field change its polarity or anything, when the current is falling?
And how about the part of the current sine wave where it cuts through the horizontal axis at 0, and changes direction? What happens to the magnetic field (and thus also to the induced back-voltage) at this point, when the current has changed direction, but is rising?
In short, I suppose I am a little confused because the relationship between SUPPLY CURRENT AND the magnetic field/induced voltage is tricky because it’s so complex:
SUMMARY OF WHAT I DON'T UNDERSTAND
AN INCREASED CHANGE IN ONE THING (current level/magnetic field) CAUSES A SIMPLE INCREASE IN ANOTHER (nduced voltage)
BUT WHAT DOES A SIMPLE INCREASE/DECREASE IN ONE THING (current level/magnetic field)CAUSE TO HAPPEN TO ANOTHER?(induced voltage)
AND WHAT DOES A CHANGE IN DIRECTION IN ONE THING (current/magnetic field) CAUSE TO HAPPEN TO ANOTHER? (induced voltage)
I’m sorry this is so long. If anyone could deal with any of my points at all, or perhaps point me in the right direction, I’d be very grateful. I may not completely understand any answers, it takes time with me, but hopefully I will progress a little more in understanding.
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