Kirchhoff's loop law represents the conservation of which physical quantity?

In the following network,$I_{1} = -0.4 \text{ A}$,$I_{4} = 1 \text{ A}$ and $I_{5} = 0.4 \text{ A}$. The values of $I_{2}$,$I_{3}$ and $I_{6}$ respectively are:

In a balanced Wheatstone bridge,the current in the galvanometer is zero. It remains zero when:

The reading of the ammeter in amperes for the following circuit is:

The galvanometer shows no deflection. What is the value of the resistance $x$ in $\Omega$?

The figure below shows a portion of an electric circuit with the currents in amperes and their directions. The magnitude and direction of the current in the portion $PQ$ is