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Question
The currents flowing in the two coils of self-inductance L1 = 16 mH and L2 = 12 mH are increasing at the same rate. If the power supplied to the two coil is equal, find the ratio of the energies stored in the two coils at a given instant ?
Solution
Energy stored, \[E = \frac{1}{2}L I^2\]
\[\frac{E_1}{E_2} = \frac{L_1 {I_1}^2}{L_2 {I_2}^2} = \frac{16}{12} \times \frac{9}{16} = \frac{3}{4}\]
\[ \Rightarrow \frac{E_1}{E_2} = \frac{3}{4}\]
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