Question

Find the equivalent emf of the three batteries as shown in the figure

• A. 4 V
• B. 8 V
• C. 2 V
• D. 1 V

Answer 1

The correct option is B 8 V

Here in given circuit, one battery is in series combination with a parallel combination of two batteries.
Hence, the equivalent emf of the three batteries ${\epsilon }_{eq}$(say) is
${\epsilon }_{eq}=4+\frac{\frac{4}{1}+\frac{4}{0.5}}{\frac{1}{1}+\frac{1}{0.5}}$
${\epsilon }_{eq}=4+\frac{12}{3}$
$\therefore {\epsilon }_{eq}=8v$