$A$ silver and zinc voltameter are connected in series and a current $i$ is passed through them for a time $t$ liberating $W \, g$ of zinc. The weight of silver deposited is nearly ..............$W$.

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

In the circuit shown in the figure,the $5\,\Omega$ resistance develops $20.00\,cal/s$ due to the current flowing through it. The heat developed in the $2\,\Omega$ resistance (in $cal/s$) is

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 temperature coefficient of resistance of tungsten is $4.5 \times 10^{-3} \, ^{\circ}C^{-1}$ and that of germanium is $-5 \times 10^{-2} \, ^{\circ}C^{-1}$. $A$ tungsten wire of resistance $100 \, \Omega$ is connected in series with a germanium wire of resistance $R$. The value of $R$ for which the resistance of the combination does not change with temperature is .......... $\Omega$.

In the Seebeck series,$Sb$ appears before $Bi$. In an $Sb-Bi$ thermocouple,the current flows from: