A magnetic field energy of $34 × 10^{-6} J$ is stored in an inductor of inductance 1.7 mH in a LC circuit. The current flowing in the inductor is
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 0.2 A
Given:
Magnetic energy, $U = 34 \times 10^{-6}\,J$
Inductance, $L = 1.7\,mH = 1.7 \times 10^{-3}\,H$
Energy stored in an inductor is given by:
$U = \frac{1}{2} L I^2$
Substitute values:
$34 \times 10^{-6} = \frac{1}{2} (1.7 \times 10^{-3}) I^2$
$I^2 = \frac{2 \times 34 \times 10^{-6}}{1.7 \times 10^{-3}} = \frac{68 \times 10^{-6}}{1.7 \times 10^{-3}} = 4 \times 10^{-2}$
$I = 0.2\,A$
∴ Current in the inductor = 0.2 A