Two cells of same emf but different internal resistances $I_{1}$ and $I_{2}$ are connected in series with a resistance $R$. The value of resistance $R$, for which the potential difference across second cell is zero, is
  • A$r _{2}- r _{1}$
  • B$r_{1}-r_{2}$
  • C$r _{1}$
  • D$r _{2}$
JEE MAIN 2022, Medium
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