Question

Two cells A and B of emf 2V and 1.5 V respectively, are connected as shown in figure through an external resistance $10\Omega$. the internal resistance of each cell is $5\Omega$. The potential difference $E_A$ and $E_B$ across the terminals of the cells A and B respectively are:

• A. $E_A=2.0V.E_B=1.5V$
• B. $E_A=2.125V,E_B=1.375V$
• C. $E_A=1.875V,E_B=1.625V$
• D. $E_A=1.875V,E_B=1.375V$

Answer 1

The correct option is C $E_A=1.875V,E_B=1.625V$

$R_{eq}=10+5+5=20\Omega$

$V_{eq}=2-1.5=0.5V$

$I=\frac{V_{eq}}{R_{eq}}I=\frac{0.5}{20}I=0.025A$

$E_A=2-R_{A}I{E}_A=2-5\ast 0.025=2-0.125=0.875V$

$E_B=1.5+R_{B}I{E}_B=1.5+5\ast 0.025=1.5+0.125=1.625V$

Hence option 'C' is correct.