Question

$n$ identical cells, each of e.m.f $\epsilon$ and internal resistance $r$ are joined in series to form a close circuit. The potential difference across any one cell is

• A. Zero
• B. $\epsilon$
• C. $\frac{\epsilon }{n}$
• D. $\frac{n-1}{n}\epsilon$

Answer 1

The correct option is A Zero

Since all cells are in series, current in circuit,

$i=\frac{n\epsilon }{nr}=\frac{\epsilon }{r}$


The equivalent circuit of one cell is shown in above figure.

The potential difference across the cell is

$V_A-V_B=\epsilon -ir=\epsilon -\frac{\epsilon }{r}r=0$