Two heaters $A$ and $B$ have power ratings of $1 \text{ kW}$ and $2 \text{ kW}$,respectively. These two are first connected in series and then in parallel to a fixed power source. The ratio of power outputs for these two cases is:

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

The Peltier coefficient for the junction of a pair of metals is proportional to:

Three wires of copper,iron,and nickel are joined to form three junctions as shown in the figure. When the temperature of junction $1$ is kept at $50\,^{\circ}\text{C}$ with the other two junctions at $0\,^{\circ}\text{C}$,the sensitive galvanometer gives a deflection of $14$ divisions. When the temperature of junction $3$ is kept at $50\,^{\circ}\text{C}$,with the other two junctions at $0\,^{\circ}\text{C}$,the galvanometer gives a deflection of $11$ divisions. Then the deflection given by the galvanometer,when the temperature of junction $2$ is kept at $50\,^{\circ}\text{C}$,with the other two junctions at $0\,^{\circ}\text{C}$,will be (in $div$)

Column $- I$ gives certain physical terms associated with the flow of current through a metallic conductor. Column $- II$ gives some mathematical relations involving electrical quantities. Match Column $- I$ and Column $- II$ with appropriate relations.

Column $- I$	Column $- II$
$(A)$ Drift Velocity	$(P)$ $\frac{m}{n e^{2} \rho}$
$(B)$ Electrical Resistivity	$(Q)$ $n e v_{d}$
$(C)$ Relaxation Period	$(R)$ $\frac{e E}{m} \tau$
$(D)$ Current Density	$(S)$ $\frac{E}{J}$

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