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JEE Main202125 Jul 2021Morning ShiftPhysicsAlternating CurrentActual

An inductor of 10 mH is connected to a 20 V battery through a resistor of 10 kΩ and a switch. After a long time, when maximum current is set up in the circuit, the current is switched off. The current in the circuit after 1 μs is x 100 mA . Then x is equal to ______ . (Take e - 1 = 0 . 37 )

Correct answer

0

Step-by-step solution

I max = V R = 20   V 10   KΩ = 2   mA For L R -decay circuit, I = I max e - R t / L I = 2   mA   e - 10 × 10 3 × 1 × 10 - 6 10 × 10 - 3 I = 2   mA   e - 1 I = 2 × 0 . 37   mA I = 74 100   mA x = 74

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