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

In the circuit shown in the figure,the capacitor $C$ is initially uncharged and the key $K$ is open. In this condition,a current of $1 \,A$ flows through the $1 \,\Omega$ resistor. The key is closed at time $t=t_0$. Which of the following statement(s) is(are) correct?

[Given: $e^{-1}=0.36$]
$(A)$ The value of the resistance $R$ is $3 \,\Omega$.
$(B)$ The current through the $3 \,\Omega$ resistor (connected in parallel to the $1 \,\Omega$ and $R$ branches) is $2 \,A$ when $K$ is open.
$(C)$ At $t=t_0+7.2 \,\mu s$,the current in the capacitor branch is $0.6 \,A$.
$(D)$ For $t < \infty$,the charge on the capacitor is $12 \,\mu C$.

The battery shown in the figure has an $e.m.f.$ $E$ and internal resistance $r$. The current in the circuit can be varied by sliding the contact $J$. If at any instant the current flowing through the circuit is $I$,the potential difference between the terminals of the cell is $V$,and the thermal power generated in the cell is equal to $\eta$ fraction of the total electrical power generated in it,then which of the following graphs is correct?

There are two electric bulbs of $40\, W$ and $100\, W$. Which one will be brighter when first connected in series and then in parallel?

Two $220\; V, 100\; W$ bulbs are connected first in series and then in parallel. Each time the combination is connected to a $220\; V\; AC$ supply line. The power drawn by the combination in each case respectively will be

Ten $60 \, W, 220 \, V$ bulbs are connected in series to a $220 \, V$ supply. The power consumed in the circuit is ......... $W$.