MCQ
What will be reading of voltmeter ................. $V$
- ✓$8.4$
- B$20$
- C$6.2$
- D$10.8$
✓
Answer
Correct option: A.
$8.4$
a
From parallel combination of cell,
From parallel combination of cell,
$\Rightarrow \mathrm{E}=\frac{\frac{20}{4}+\frac{6}{3}}{\frac{1}{4}+\frac{1}{3}}=12$ $\mathrm{volt}$ $\Rightarrow \mathrm{r}=\frac{12}{7}$
$\Rightarrow \mathrm{V}=4\left[\frac{12}{4+\frac{12}{7}}\right]=8.4 \mathrm{\,volt}$
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