Two cells of $emfs$ $E_1$ and $E_2$ and internal resistances $r_1$ and $r_2$ are connected in parallel. The $emf$ and internal resistance of the equivalent source is
  • A${E_1}\, + \,{E_2}$  and  $\frac{{{r_1}{r_2}}}{{{r_1} + {r_2}}}$
  • B${E_1}\, - \,{E_2}$  and  $r_1\, +\, r_2$
  • C$\frac{{{E_1}{r_2}\, + \,\,{E_2}{r_1}}}{{{r_1} + {r_2}}}$  and  $\frac{{{r_1}{r_2}}}{{{r_1} + {r_2}}}$
  • D$\frac{{{E_1}{r_2}\, + \,\,{E_2}{r_1}}}{{{r_1} + {r_2}}}$  and  $r_1\, +\, r_2$
Medium
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