$A$ thermocouple develops $200\,\mu V$ between $0\,^{\circ}C$ and $100\,^{\circ}C$. If it develops $64\,\mu V$ and $76\,\mu V$ respectively between $(0\,^{\circ}C - 32\,^{\circ}C)$ and $(32\,^{\circ}C - 70\,^{\circ}C)$,then what will be the thermo-emf it develops between $70\,^{\circ}C$ and $100\,^{\circ}C$ in $\mu V$?

The terminal voltage $V$ across a battery of $emf$ $E$ and internal resistance $r$ can be:

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

The cold junction of a thermocouple is at $0^{\circ} C$. The thermo e.m.f. produced in the thermocouple is given by the equation $E = 16T - 0.04T^2$, where $T$ is the temperature of the hot junction. The temperature of inversion and the neutral temperature of the thermocouple are:

The heater of an electric kettle is made of a wire of length $L$ and diameter $d$. It takes $4$ minutes to raise the temperature of $0.5 \ kg$ of water by $40 \ K$. This heater is replaced by a new heater having two wires of the same material,each of length $L$ and diameter $2d$. The way these wires are connected is given in the options. How much time in minutes will it take to raise the temperature of the same amount of water by $40 \ K$?
$(A)$ $4$ if wires are in parallel
$(B)$ $2$ if wires are in series
$(C)$ $1$ if wires are in series
$(D)$ $0.5$ if wires are in parallel

The figure shows a network of four resistances and three batteries. The electrical power dissipated as heat in the circuit is .............. $W$.