In the given circuit, an ideal voltmeter connected across
Question:

In the given circuit, an ideal voltmeter connected across the $10 \Omega$ resistance reads $2 \mathrm{~V}$. The internal resistance $\mathrm{r}$, of each cell is :

  1. (1) $1 \Omega$

  2. (2) $0.5 \Omega$

  3. (3) $1.5 \Omega$

  4. (4) $0 \Omega$


Correct Option: , 2

Solution:

(2) For the given circuit

$\mathrm{i}=\frac{3}{8+2 \mathrm{r}}$

Now voltage across $\mathrm{AB}$

$\mathrm{i} \times 6=\frac{3}{8+2 \mathrm{r}} \times 6=2$

$\Rightarrow 9=8+2 \mathrm{r}$

$\Rightarrow \mathrm{r}=\frac{1}{2} \Omega$

Administrator

Leave a comment

Please enter comment.
Please enter your name.