Two batteries, one of emf \(18~\text{V}\) and internal resistance \(2~\Omega\) and the other of emf \(12~\text V\) and internal resistance \(1~\Omega,\) are connected as shown. Reading of the voltmeter is:
(if a voltmeter is ideal)
1. \(14~\text V\)
2. \(15~\text V\)
3. \(18~\text V\)
4. \(30~\text V\)
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. |