Which of the following equations represents the Gauss's law in a homogeneous isotropic medium?

In the circuit shown in fig, $$L$$ is large and the average value of $$'i'$$ is $$100A.$$ The thyristor is gated in the half cycle of $$'e'$$ at a delay angle $$\alpha $$ equal to ___________.
$$e\left( t \right) = \sqrt 2 .00\,\,\sin \,\,314t$$

The selection of size of conductors for a distributor in a distribution system is governed by

The inductance of a power transmission line increases with