Q. Two cells of e.m.f. $E_{1}$ and $E_{2}$ are joined in series and the balancing length of the potentiometer wire is $625\, cm$. If the terminals of $E_{1}$ are reversed, the balancing length obtained is $125 \,cm$. Given $E_{2} > E_{1}$, the ratio $E_{1}: E_{2}$ will be
Current Electricity
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