In the circuit of the adjoining figure,the current through the $12 \ \Omega$ resistor will be ................ $A$.

$A$ conductor is made of an isotropic material and has the shape of a truncated cone. $A$ battery of constant emf is connected across it and its left end is earthed as shown in the figure. If at a section distant $x$ from the left end, electric field intensity, potential, and the rate of generation of heat per unit length are $E, V$, and $H$ respectively, which of the following graphs is/are correct?

When a current passes through the junction of two different metals,the evolution or absorption of heat at the junction is known as:

Six similar bulbs are connected as shown in the figure with a $DC$ source of $emf\; E$,and zero internal resistance. The ratio of power consumption by the bulbs when $(i)$ all are glowing and $(ii)$ in the situation when two from section $A$ and one from section $B$ are glowing,will be

The two ends of a uniform conductor are joined to a cell of $e.m.f.$ $E$ and some internal resistance. Starting from the midpoint $P$ of the conductor,we move in the direction of current and return to $P$. The potential $V$ at every point on the path is plotted against the distance covered $(x)$. Which of the following graphs best represents the resulting curve?

Find the percentage error in the reading of the voltmeter shown in the circuit. (in $\%$)