Question 7.22: A solenoid with resistance 4 Ω and inductance 6 mH is used i...

Fundamentals of Electric Circuits

A solenoid with resistance 4 Ω and inductance 6 mH is used in an auto-mobile ignition circuit similar to that in Fig. 7.78. If the battery supplies 12 V, determine: the final current through the solenoid when the switch is closed, the energy stored in the coil, and the voltage across the air gap, assuming that the switch takes 1 µs to open.

7.78

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