If the resistance of the voltmeter is $10000 \,\Omega$ and the resistance of the ammeter is $2 \,\Omega$,find the value of $R$ when the voltmeter reads $12 \,V$ and the ammeter reads $0.1 \,A$.

$A$ cell whose e.m.f. is $2\, V$ and internal resistance is $0.1\,\Omega$ is connected with a resistance of $3.9\,\Omega$. The voltage across the cell terminal will be ................ $V$.

What is the current $i$ in the circuit as shown in the figure (in $A$)?

The internal resistances of two cells shown in the figure are $0.1\,\Omega$ and $0.3\,\Omega$. If $R = 0.2\,\Omega$,find the potential difference across the cells.

The diagram shows a circuit used in an experiment to determine the $emf$ $(E)$ and internal resistance $(r)$ 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?

In the given circuit,$E_1 = E_2 = E_3 = 2 \, V$ and $R_1 = R_2 = 4 \, \Omega$. What is the current flowing between points $A$ and $B$ (in $, A$)?