Grouping Of Cells

Two cells having the same emf, are connected in series through an external resistance R. Cells have internal resistance r₁ and r₂ respectively. When the circuit is closed, the potential difference across the first cell is zero. The value of R is:

1. $r_1-r_2$

2. $\frac{r_1+r_2}{2}$

3. $\frac{r_1-r_2}{2}$

4. $r_1+r_2$

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

1.		2.
3.		4.

For the circuit shown in the figure, the current will be: