Question

Two cells are connected between points $A$ and $B$ as shown. Cell 1 has emf of $12V$ and internal resistance of $3\Omega$. Cell 2 has emf of $6V$ and internal resistance of $6\Omega$. An external resistor $R$ of $4\Omega$ is connected across $A$ and $B$. The current flowing through $R$ will be ___ $A$.

Answer 1

Answer: 1

$E_{eq}=\frac{\frac{12}{3}-\frac{6}{6}}{\frac{1}{3}+\frac{1}{6}}$
$E_{eq}=6V$
$r_{eq}=2\Omega$
$R=4\Omega$