1. Tardigrade
  2. Question
  3. Physics
  4. A circuit has a self inductance of 1 Henry and carries a current of 2 A. To prevent sparking when the circuit is switched off, a capacitor which can withstand 400 V is used. The least capacitance of the capacitor connected across the switch must be equal to

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. A circuit has a self inductance of $1$ Henry and carries a current of $2\, A$. To prevent sparking when the circuit is switched off, a capacitor which can withstand $400\, V$ is used. The least capacitance of the capacitor connected across the switch must be equal to

KCETKCET 2022

Solution:

$1 / 2\, CV ^{2}=1 / 2 LI ^{2}$
therefore, $C = L I ^{2} / V ^{2}=1 \times 2^{2} / 400^{2}=25\, \mu F$