I have spent a lot of time thinking about Faraday's law and common explanation as given on wikipedia does not sit well with me. I may be confused. My concern is entirely with the wording of this explanation From wiki:
"The increase in current causes a back EMF (voltage) across the inductor due to Faraday's law of induction which opposes the change in current."
So the above says that polarity of emf is opposite the change in current. I interpret this as the induced voltage across the inductor will have a polarity such that it would create a current opposing the change in current which produced it. This makes sense as the induced voltage exists because the inductor tries to maintain its magnetic field. For increasing current then, as more current is flowing from source to ground, the current (call it I') which would oppose this change flows from ground to source. The voltage which would be associated with this I' is in the opposite direction of the actual induced voltage, because the strengthening magnetic field due to increasing current actually causes the inductor to push positive current from ground to source, which is really sending positive charge into the source-side of the inductor. So, like we see in the figure below, the induced voltage appears on the source side of the battery. The same as the changing current. Which agrees with V = Ldi/dt. So why do they explain it as "emf opposes change in current" ? Seems to me that emf has same polarity as change in current. Can someone please offer some clarification?
To put it another way, looking at the situation below where the the switch closes, current begins to flow so di/dt > 0, then we know induced voltage V > 0. So from the way we define positive current in the circuit, and the equation V = Ldi/dt, the induced voltage should be positive on the source side (inductor side 1 as shown below). This agrees with the figure but not with the wording of the explanation. Because the change in current is positive, current is increasing from source-> ground, the opposing current which OPPOSES this change would be flowing from the ground->source. The voltage which would be associated with this opposing current would then be positive on the ground side relative to the source side, but this is opposite what we see in the figure below and the equation V = Ldi/dt. So why would they put this explanation on wikipedia? Which should be the most clear and eloquent explanation of this mathematical relationship?
Thank you for taking the time to read and respond!