A battery consists of a variable number \(n\) of identical cells (having internal resistance \(r\) each) which are connected in series. The terminals of the battery are short-circuited and the current \(I\) is measured. Which of the graphs shows the correct relationship between \(I\) and \(n?\)

1.		2.
3.		4.

For the circuit shown in the figure, the current \(I\) will be:

Two batteries, one of emf \(18\) volts and internal resistance \(2~\Omega\) and the other of emf \(12\) V and internal resistance \(1~\Omega,\) are connected as shown. The voltmeter \(\mathrm{V}\) will record a reading of: 

1. \(18\) V
2. \(30\) V
3. \(14\) V
4. \(15\) V