The figure shows a network of resistances in which the point $A$ is earthed. The current through the $4\,\Omega$ resistor is

The emf of a thermocouple,one junction of which is kept at $0\,^{\circ}C$,is given by $e = at + bt^2$. The Peltier coefficient will be

In the circuit shown, the heat produced in $5 \Omega$ resistance due to current $I_2$ is $50 \text{ J/s}$. Then, the heat generated per second in $2 \Omega$ resistance is (in $\text{ J/s}$)

When subjected to a voltage of $10 \, V$, the current through a resistor at a temperature of $40^{\circ} C$ is $0.1 \, A$. The temperature coefficient of resistance of the material of the resistor is $2 \times 10^{-4} {}^{\circ} C^{-1}$. The temperature of the resistor in ${}^{\circ} C$ when the current drops to $0.098 \, A$ is

In steady state, the potential difference across the capacitor is $10\, V$. Each resistance is of $3\, \Omega$. The cell is ideal. The $emf$ of the cell is ............. $V$.

For what value of resistance $R$ in the given circuit will the galvanometer reading be zero (in $\Omega$)? The internal resistance of both batteries is negligible.