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

Kirchhoff's first law,$i.e.$,$\Sigma i = 0$ at a junction,is based on the law of conservation of:

The equivalent resistance between $A$ and $B$ in the given circuit is . . . . . . . . (in $\Omega$)

In the network shown in the figure,each of the resistance is equal to $2\,\Omega$. The resistance between the points $A$ and $B$ is .............. $\Omega$.

Figure $(i)$ below shows a Wheatstone's bridge in which $P, Q, R$ and $S$ are fixed resistances,$G$ is a galvanometer and $B$ is a battery. For this particular case,the galvanometer shows zero deflection. Now,only the positions of $B$ and $G$ are interchanged,as shown in figure $(ii)$. The new deflection of the galvanometer

Refer to the circuit diagram given below. The heat generated across the $6\text{ }\Omega$ resistance in $100\text{ s}$ is $\frac{\alpha}{100}\text{ J}$. The value of $\alpha$ is . . . . . . . (Nearest integer)