Question

In Walter Lewin's lecture explaining RL circuits, he says:
"The electric field in the self-inductance is 0 because the self-inductance has no resistance, it's super-conducting material."

I understand that the inductor has no resistance, but why does that mean that the electric field is zero here?

Thank you!

Answer 1

Via Ohms Law,
\[R = \frac{\Delta V}{I} = 0 \rightarrow \Delta V = 0\]
The electric field is
\[E = -\frac{dV}{dx} \]
And since the voltage is constant, E is the derivative of a constant, or zero.

Answer 2

thank you! :)