A battery (V-9V) is connected with a resistor R1000 ohms and an inductor L 0.5mH. The circuit initially contains an open switch and at t 0, the switch is closed.a) what is the time circuit?b) Determine the Maximum current flowing in the circuit
The time constant for an RL circuit L/R (remember that L*Amps/second Amps*R so L/R has units of seconds). L/R 0.5e-3/1e3 0.5e-6 s R/L 2e6 2,000,000 After a long time an inductor is modeled as a short circuit when the current is a maximum V/R V/R 9/1000 9e-3 A 9 ma. iL(t) 9ma*[1-e^-t/(L/R)] 9ma*[1-e^-Rt/L] 9ma*[1-e^-2,000,000*t] After 5 time constants 2.5e-6 e^-2e6*2.5e-6 e^-5 iL(5*L/R) iL(2.5e-6) 9ma*(1-e^-5) 8.94ma which is 99.33% it's maximum value after only 2.5μs
