The direction of current in an iron-copper thermocouple is

One junction of a certain thermoelectric couple is at a fixed temperature $T_r$ and the other junction is at temperature $T$. The thermo electromotive force for this is expressed by $E = K(T - T_r) \left[ T_0 - \frac{1}{2}(T + T_r) \right]$. At temperature $T = \frac{1}{2}T_0$,the thermoelectric power is

Which of the following circuits follows Ohm's law?

Two wires with resistances $R$ and $2R$ are connected in parallel. The ratio of heat generated in $2R$ and $R$ is:

The resistance of a wire is $10^{-6} \, \Omega$ per meter. It is bent in the form of a circle of diameter $2 \, m$. A wire of the same material is connected across its diameter. The total resistance across its diameter $AB$ will be

$A$ $100 \ W$ bulb is rated at $200 \ V$ and a $200 \ W$ bulb is rated at $100 \ V$. Then: