$A$ silver voltmeter and a copper voltmeter are connected in parallel to a $12\ V$ battery. In $30\ minutes$,$1\ g$ of silver and $1.8\ g$ of copper are deposited. The power supplied by the battery is .... $(Z_{Cu} = 6.6 \times 10^{-4}\ g/C$ and $Z_{Ag} = 11.2 \times 10^{-4}\ g/C)$ (in $J/s$)

In the circuit as shown in the figure, the:

For a thermocouple,the temperature of inversion is that temperature at which the thermo $e.m.f.$ is:

The resistance of the filament of a lamp increases with the increase in temperature. $A$ lamp rated $100\, W, 220\, V$ is connected across a $220\, V$ power supply. If the voltage drops by $10\%$,then the power of the lamp will be:

First,a set of $n$ equal resistors of $10 \; \Omega$ each are connected in series to a battery of emf $20 \; V$ and internal resistance $10 \; \Omega$. $A$ current $I$ is observed to flow. Then,the $n$ resistors are connected in parallel to the same battery. It is observed that the current is increased $20$ times. The value of $n$ is .... .

Two resistors with resistances $R_1$ and $R_2$ are connected in series and two capacitors with capacitances $C_1$ and $C_2$ are also connected in series. These two systems are connected to a battery of $EMF$ $\varepsilon$ as shown in the figure. The potential difference between points $a$ and $b$ is zero in the steady state if: