$A$ cell of internal resistance $r$ is connected across an external resistance $n r$. Then the ratio of the terminal voltage to the emf of the cell is

$A$ resistor is connected to a battery of $12 \text{ V}$ emf and internal resistance $2 \text{ }\Omega$. If the current in the circuit is $0.6 \text{ A}$, the terminal voltage of the battery is: (in $\text{ V}$)

The current flowing through the circuit shown in the figure is ........... $A$.

$A$ copper voltameter and a silver voltameter are connected in parallel. When a total charge $q$ flows through the voltameters,an equal mass of metal is deposited in each. If the electrochemical equivalents of copper and silver are $z_1$ and $z_2$ respectively,then the charge flowing through the silver voltameter is:

In the circuit element given here,if the potential at point $B$,$V_B = 0$,then the potentials of $A$ and $D$ are given as

For which value of resistance $R$ does the galvanometer show zero deflection in the electrical circuit shown below (in $\Omega$)?