The magnetic potential energy stored in a certain inductor is $25 ext{ mJ}$, when the current in the inducto

Question

The magnetic potential energy stored in a certain inductor is $25 	ext{ mJ}$, when the current in the inductor is $60 	ext{ mA}$. This inductor is of inductance:

Accepted Answer

The magnetic potential energy ($U$) stored in an inductor is given by the formula:
$$ U = \frac{1}{2} L I^2 $$
Where:
*   $U$ is the energy stored ($25 	ext{ mJ} = 25 	imes 10^{-3} 	ext{ J}$)
*   $I$ is the current flowing ($60 	ext{ mA} = 60 	imes 10^{-3} 	ext{ A}$)
*   $L$ is the self-inductance of the inductor.

**Calculation:**
Rearranging the formula to solve for $L$:
$$ L = \frac{2U}{I^2} $$
$$ L = \frac{2 	imes (25 	imes 10^{-3} 	ext{ J})}{(60 	imes 10^{-3} 	ext{ A})^2} $$
$$ L = \frac{50 	imes 10^{-3}}{3600 	imes 10^{-6}} $$
$$ L = \frac{50 	imes 10^{-3}}{3.6 	imes 10^{-3}} $$
$$ L = \frac{50}{3.6} \approx 13.888... 	ext{ H} $$

Rounding to two decimal places, the inductance is $13.89 	ext{ H}$.

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