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> The mystery is in saying that there is actually "no voltage", and the
> current is just magically flowing all by itself.
Well, the quick way to explain is to look up the formula for an inductor:
V(t) = L * dI / dt
So, the voltage is proportional to the rate of change of current. This is
because a magnetic field is generated by the flowing current, and when the
current changes the magnetic field generates a reverse-voltage to try and
cancel out the current change.
Nowhere does it say that a voltage of zero means no current flows.
If you've got 5 V and 5 A flowing through an inductor and you then suddenly
switch the current to 10 A, it's quite possible that the inductor will
generate a back-emf of -5V (so giving a sum of zero across the inductor) to
try and keep the current at 5A. During the split second that the voltage is
zero, it is behaving exactly like a piece of wire with no resistance.
Or for a capacitor:
I(t) = C * dV / dt
This says that the current is proportional to the rate of change of voltage.
Nowhere does it say that no current can flow if the voltage is zero. But,
note, the rate of change of voltage can't be zero, otherwise no current
would flow.
But for a resistor:
V(t) = I(t) * R
In this case, I=0 means V=0 whatever is going on (for non-zero R)
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