The current in a simple series circuit is $5.0 \, A$. When an additional resistance of $2.0 \, \Omega$ is inserted, the current drops to $4.0 \, A$. The original resistance of the circuit in $\Omega$ was:

In the circuit shown, the heat produced in $5 \Omega$ resistance due to current $I_2$ is $50 \text{ J/s}$. Then, the heat generated per second in $2 \Omega$ resistance is (in $\text{ J/s}$)

In the given circuit, the current through the $2 \Omega$ resistor is: (in $\text{ A}$)

Four ammeters with identical internal resistance $r$ and a resistor $R$ are connected to a current source as shown. If the readings of $A_1$ and $A_2$ are $3 \, A$ and $5 \, A$ respectively,then the reading of $A_4$ is ............. $A$.

The storage battery of a car has an emf of $12 \ V$. If the internal resistance of the battery is $0.6 \ \Omega$,then the maximum current that can be drawn from the battery is . . . . . . . (in $A$)

$A$ storage battery of $emf$ $8.0\; V$ and internal resistance $0.5\; \Omega$ is being charged by a $120\; V$ $DC$ supply using a series resistor of $15.5\; \Omega$. What is the terminal voltage of the battery during charging? What is the purpose of having a series resistor in the charging circuit?