When a current is passed through water,acidified with a dilute sulphuric acid,the gases formed at the platinum electrodes are

The figure shows a tetrahedron,each side of which has a resistance $r$. Choose the correct diagram$(s)$,which show a two-dimensional equivalent of the tetrahedron.

Consider the following statements $A$ and $B$ and identify the correct answer given below.
$A$. Peltier coefficient is numerically equal to the potential difference across the junctions of the thermocouple through which current is flowing.
$B$. According to Thomson, energy is neither absorbed nor evolved at the junction of a thermocouple but is absorbed or evolved only along the lengths of both the conductors.

$A$ room has an $AC$ running for $5$ hours a day at a voltage of $220$ $V$. The wiring of the room consists of $Cu$ wire of $1$ $mm$ radius and a length of $10$ $m$. Power consumption per day is $10$ commercial units. What fraction of it goes into Joule heating in the wires? What would happen if the wiring is made of aluminium of the same dimensions? $(\rho_{Cu} = 1.7 \times 10^{-8} \, \Omega m, \rho_{Al} = 2.7 \times 10^{-8} \, \Omega m)$

The ends of an element of zinc wire are kept at a small temperature difference $\Delta T$ and a small current $I$ is passed through the wire. Then, the heat developed per unit time

If $E$ denotes the electric field in a uniform conductor,$I$ the corresponding current through it,${v_d}$ the drift velocity of electrons,and $P$ the thermal power produced in the conductor,then which of the following graphs is incorrect?