In a potentiometer arrangement $E_1$ is the cell establishing current in primary circuit $E_2$ is the cell to be measured. $AB$ is the potentiometer wire and $G$ is a galvanometer. Which of the following are the essential condition for balance to be obtained

 Consider an infinte ladder network shown in figure. A voltage $V$ is applied between the points $A$ and $B$. This applied value of voltage is halved after each section.
  

In the diagram resistance between any two junctions is $R$. Equivalent resistance across terminals $A$ and $B$ is

The diagram besides shows a circuit used in an experiment to determine the emf and internal resistance of the cell $C$. A graph was plotted of the potential difference $V$ between the terminals of the cell against the current $I,$ which was varied by adjusting the rheostat. The graph is shown on the right; $x$ and $y$are the intercepts of the graph with the axes as shown. What is the internal resistance of the cell?

A battery is of emf $E$ is being charged from a charger such that positive terminal of the battery is connected to terminal $A$ of charger and negative terminal of the battery is connected to terminal $B$ of charger. The internal resistance of the battery is $r$.

A battery of emf $E$ and internal resistance $r$ is connected across a resistance$R.$ Resistance $R$ can be adjusted to any value greater than or equal to zero. A graph is plotted between the current $\left(i\right)$ passing through the resistance and potential difference $\left(V\right)$ across it. Select the correct alternative.