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JEE Main202622 January 2026Morning ShiftPhysicsElectromagnetic InductionActual

Inductance of a coil with 10⁴ turns is 10 mH and it is connected to a dc source of 10 V with internal resistance of 10 . The energy density in the inductor when the current reaches ( 1 e ) of its maximum value is 1 e² ~J / m ³ . The value of is _ _ _ _ . ( ₀=4 10⁻⁷ Tm / A ).

Correct answer

0

Step-by-step solution

L =10 10⁻³ H N =10^4 I₀= 10 10 =1 ~A (max current) I= 1 e E_ d = B^2 2 ₀ B= ₀ n I L= ₀ n^2 R^2 E_d= ₀ n^2 I^2 2 = 4 10⁻⁷ 10^8 1 e ^2 2 = 20 e ^2

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