RLC Switching - Initial Condition
In the above circuit (with DC source), the switch closes at . Prior to closing, the inductor and capacitor are completely de-energized.
What is the magnitude of the current through the capacitor immediately after the switch closes?
The answer is 10.
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1 solution
The main principles are:
1) The voltage across a capacitor cannot change discontinuously
2) The current through an inductor cannot change discontinuously
When the switch closes, the capacitor voltage and inductor current are zero. This implies the following:
1) The right side of the resistor is at reference potential
2) The current through the resistor is 10 amps
3) The current through the capacitor is equal to the current through the resistor (since the inductor current is zero)
4) The capacitor current is 10 amps