Engineering Board Exam Reviewer · Time Response of Reactive Circuits · easy
In the circuit shown the capacitor is uncharged when the switch closes at t=0 (V=30 V, R=5 k , C=10, F). What current flows in the circuit at the instant t=0+?
- 6 mA
- 0 A
- 3.79 mA
- 3 mA
Answer
A. 6 mA
Solution
At t=0+ the uncharged capacitor acts as a short circuit, so the full source voltage appears across R: i(0+)=V/R= 30 V5 k =6 mA.
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