Question 464: AC fundamentals

Question

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

Accepted Answer

From question energy stored in inductor,
U = 25 ÃÂ 10
Ã¢ÂÂ3
J
Current, I = 60 mA
Also, energy stored in inductor, U = $${1 \over 2}L{I^2}$$
25 ÃÂ 10
Ã¢ÂÂ3
= $${1 \over 2} 	imes L 	imes {\left( {60 	imes {{10}^{ - 3}}} ight)^2}$$
$$ \Rightarrow $$ L = $${{25 	imes 2 	imes {{10}^6} 	imes {{10}^{ - 3}}} \over {3600}}$$ = 13.89 H

Answer

0.138 H

Answer

138.88 H

Answer

1.389 H

Answer

13.89 H

AC fundamentals

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

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