Question

Case study $\left(1\right)$

A car battery with a $12\text{V}$ emf and an internal resistance of $0.04\Omega$ is being charged with a current of $50\text{A}$.

$\left(i\right)$The potential difference $\text{V}$ across the terminals of the battery is

• A. $10\text{V}$
• B. $14\text{V}$
• C. $16\text{V}$
• D. $12\text{V}$

Answer 1

The correct option is B $14\text{V}$

Given, $\text{EMF}$ of the battery , $E=12\text{V}$

Internal resistance, $r=0.04\Omega$

The given battery is charging with current, $i=50\text{A}$

During charging, $V>E$

$V=E+ir$

$=12+(50\times 0.04)$

$=12+2$

$V=14\text{V}$

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Hence, $\left(B\right)$ is the correct answer.