An inductor coil stores 64 J of magnetic field energy and dissipates energy at the rate of 640 W when a current of 8A is passed through it. If this coil is joined across an ideal battery, find the time constant of the circuit in seconds :
Solution
$U = {1 \over 2}L{i^2} = 64 \Rightarrow L = 2$<br><br>${i^2}R = 640$<br><br>$R = {{640} \over {{{(8)}^2}}} = 10$<br><br>$\tau = {L \over R} = {1 \over 5} = 0.2$
About this question
Subject: Physics · Chapter: Electromagnetic Induction · Topic: Self and Mutual Inductance
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