Kirchhoff´s rule is for the birds; Walter Lewin on circuits in changing magnetic fields
Why Physics Stack Exchange recommends it
Physics Stack Exchange users link it when explaining or questioning how potential differences and electric fields behave in circuits with inductors, since it works the problem from Faraday's law.
Recommended by 2 people across 2 different months, 2018 to 2019.
What it is
A 16-minute re-upload of a Walter Lewin lecture on circuits that sit in changing magnetic fields. Lewin argues that Kirchhoff's loop rule fails when an inductor is present and works through the circuit using Faraday's law instead.
What people said
Recommends Ján Lalinský · 2018-07 · Physics Stack Exchange · on “Is there a potential difference across an inductor”
You probably misunderstood what Lewin is saying. I watched one of his lectures where he deals with inductor in a circuit and he gets the potential differences correctly, including the inductor. Here is the video of the lecture: [this video] What he is criticizing is a different thing - that teachers and textbook authors explain Kirchhoff's law in circuits with inductors incorrectly: they assume $$ \oint \mathbf E\cdot d\mathbf s = 0 $$ is valid even for circuit with inductor (it is not) and then rewrite this using partial integrals across the elements in the circuit, assuming (again incorrectly) that the integral over the wire of the inductor is $+LdI/dt$ (in fact, the integral is much lower and
Recommends user233089 · 2019-07 · Physics Stack Exchange · on “Is the flow of charges in inductor though electric field zero?”
How electric field inside the wire of an inductor is zero (i.e. material of which loop is made — note material is assumed to be a superconductor), then how electrons flow in an inductor if electric field inside wire of inductor is zero? This question struck in my mind when I was applying Faraday's law to circuit having an inductor. Please explain in LR circuit. Professor Walter Lewin video [this video] . In this video professor Walter Lewin says that electric field would be zero but does not explain it in detail and also does not explain about how charges flow when electric field is zero. It may be better if you watch this video before answering my doubt
Cites user31058 · 2018-02 · Physics Stack Exchange · on “Kirchhoff law and Inductors”
I am struggling with using Kirchhoff's rule in circuits with Inductors. Looks like if you have an inductor, we have Electric field (E) that is created using a time varying magnetic field and that E is non conservative and hence you will have to use Faraday's and not Kirchhoff's rule. I get that. But when you use Faraday's rule, Electric field within inductor is taken to be zero as it has zero resistance. I don't get the connection of zero resistance and zero electric field. Below is link where Prof Lewin uses Faraday's law. I get everything in this video other than why E should be zero within the inductor [this video]