Question

An inductance of $2H$ carries a current of $2A$. To prevent sparking when the circuit is broken a capacitor of $4\mu F$ is connected across the inductance. The voltage rating of the capacitor is of the order of :

• A. ${10}^{3}V$
• B. $10V$
• C. ${10}^{5}V$
• D. ${10}^{6}V$

Answer 1

The correct option is A ${10}^{3}V$

$\frac{1}{2}L{i}^2=\frac{1}{2}C{V}^2$
$\therefore V=\sqrt{\frac{L}{C}}i=\sqrt{\frac{2}{4\times {10}^{-6}}}\left(2\right)=\sqrt{2}\times {10}^{3}V$