In the given circuit, an ideal voltmeter connected across th... | Physics | SolveeIt | Solveeit

Today, August 18

Question

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

A

$1 \Omega$

B

$1.5 \Omega$

C

$0\Omega$

D

$0.5\Omega$

Answer

$0.5\Omega$

Explanation

Solution

$R_{eq} = \frac{15\times10}{25} + 2 +2r$
$= 8 + 2r$
$i = \frac{3}{ 8+2r}$
$2 = i R_{eq} = \frac{3}{8 + 2 r } \times6$
$16 +4r = 18$
$\Rightarrow r = 0.5 \Omega$