A (i) series (ii) parallel combination of two given resistors is connected, one by one, across a cell. In which case will the terminal potential difference, across the cell have a higher value?
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Terminal potential difference across a cell,
$\text{V}=\varepsilon-\text{lr}$
In series arrangement, current, $\text{I}_\text{S}=\frac{\text{E}}{\text{R}_1+\text{R}_2+\text{r}}$
In parallel arrangement, current, $\text{I}_\text{P}=\frac{\text{E}}{\frac{\text{R}_1\text{R}_2}{\text{R}_1+\text{R}_2}+1}$
Obviously, IP > IS, so VP < VS.
That is series arrangement will have higher terminal potential difference.
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