For a cell, the graph between the potential difference $(V)$ across the terminals of the cell and the current $(I)$ drawn from the cell is shown in the figure. The $e.m.f.$ and the internal resistance of the cell are

$A$ student was trying to construct the circuit shown in the figure below marked $(a)$,but ended up constructing the circuit marked $(b)$. Realising her mistake,she corrected the circuit,but to her surprise,the output voltage (across $R$) did not change. The value of resistance $R$ is ............ $\Omega$

An electrical circuit consists of ten $100 \,\Omega$ resistors. Out of these $10$ resistors,a group of $n_1$ resistors are connected in parallel and another group of $n_2$ resistors are separately connected in parallel. These two groups are then connected in series and this combination is connected to a voltage source of $100 \,V$. If the net current through the circuit is $2.5 \,A$,the values of $n_1$ and $n_2$ are:

In the circuit shown,the current through $R_2$ is zero. If $R_4 = 2\,\Omega$ and $R_3 = 4\,\Omega$,the current through $R_3$ will be ................. $A$.

Resistances of $6\, \Omega$ each are connected in the manner shown in the adjoining figure. With the current $0.5\, A$ as shown in the figure, the potential difference $V_P - V_Q$ is .............. $V$.

The current from the battery in the circuit diagram shown is .............. $A$.