$A$ battery with an internal resistance of $4\,\Omega$ is connected to a circuit as shown in the figure. For the circuit to receive maximum power,the value of $R$ should be ..... $\Omega$.

What is the current $I$ (in $A$) flowing through the given circuit?

In the given circuit,the reading of the ideal voltmeter is $\frac{E}{2}$. Find the internal resistance $r$ of the cell in $\Omega$.

$A$ voltmeter connected across the terminals of a battery reads $5\,V$. When an ammeter is connected across the same terminals,it reads $10\,A$. If a resistor of $2\,\Omega$ is connected across the terminals of this battery,the current flowing through it will be ...........$A$.

In the given circuit diagram,the current through the battery and the charge on the capacitor,respectively,in the steady state are:

An infinite line charge of uniform electric charge density $\lambda$ lies along the axis of an electrically conducting infinite cylindrical shell of radius $R$. At time $t=0$,the space inside the cylinder is filled with a material of permittivity $\varepsilon$ and electrical conductivity $\sigma$. The electrical conduction in the material follows Ohm's law. Which one of the following graphs best describes the subsequent variation of the magnitude of current density $j(t)$ at any point in the material?