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Circuit diagram from the videoAn inductor is connected to an AC generator. Suppose no resistance or capacitor is connected to that circuit.

Then as per the lesson in khan academy, it's said that the inductor and the source voltage have the same polarity at any point of time since the inductor tries to resist the change in current. However, shouldn't the polarity be opposite to that of the source voltage since current flows from higher to lower voltage and to resist that flow? Or is this notion wrong? Video Link For More Context If Required

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    $\begingroup$ The polarity of anything you connect to a generator through zero resistance matches the voltage and polarity of the generator. Otherwise, the current flow is (ideally) infinite. $\endgroup$
    – John Doty
    Commented Mar 13, 2023 at 18:22
  • $\begingroup$ Always include a circuit diagram with circuit questions. $\endgroup$
    – DanielSank
    Commented Mar 13, 2023 at 22:16
  • $\begingroup$ @JohnDoty But the explanation that the inductor is having the same polarity because it's trying to oppose increase in current shouldn't be accurate in that case, right? $\endgroup$
    – Light Breeze
    Commented Mar 15, 2023 at 4:34
  • $\begingroup$ @DanielSank Added it from the video, is it ok? $\endgroup$
    – Light Breeze
    Commented Mar 15, 2023 at 4:38
  • $\begingroup$ @LightBreeze The inductance controls the current for that results from an applied voltage. The applied voltage from a generator is whatever the generator makes. $\endgroup$
    – John Doty
    Commented Mar 15, 2023 at 13:50

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As the current increases the inductor will try to oppose the change in current(as u said) by generating the polarity across it's ends.

From the video the source is trying to flow current in clockwise direction and when the current increases the inductor will try to flow current in anti-clockwise directions means on left side +ve will be induced and on right side -ve will be induced

For easy understanding think of it as a battery (replace the source voltage and inductor with a battery) 1st battery(AC source) is trying to flow current in clockwise direction now if another battery(inductor in our case with +ve on left side and -ve on right side) it will try to flow current in opposite direction and ultimately the net current in the circuit will be reduced and will flow in direction of battery with higher potential

I hope its clear you can comment if you are getting any doubts(cause I think I messed up in explaining that's why I gave you an example hope it's clear by example) :)

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  • $\begingroup$ Sorry but I am confused about this exactly, if the inductor tries to flow current in anti clockwise direction shouldn't +ve be induced on the left? Since current flows from +ve to -ve? $\endgroup$
    – Light Breeze
    Commented Mar 15, 2023 at 4:41
  • $\begingroup$ but how will current flow in open circuit? it should be closed $\endgroup$
    – Shardul
    Commented Mar 15, 2023 at 15:24
  • $\begingroup$ The circuit is closed though? $\endgroup$
    – Light Breeze
    Commented Mar 16, 2023 at 6:26
  • $\begingroup$ @LightBreeze no, What I'm trying to say is that if in inductor the +ve is on right and -ve on left(as you are saying ) then don't you think that it will support source current to increase as current in inductor will flow in clockwise direction rather than in anticlockwise direction? $\endgroup$
    – Shardul
    Commented Mar 16, 2023 at 6:44

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