Engineering Board Exam Reviewer · Time Response of Reactive Circuits · easy
At the instant a switch connects an uncharged capacitor to a dc voltage source through a resistor, the capacitor behaves like a
- short circuit
- open circuit
- constant current source
- resistor of value R
Answer
A. short circuit
Solution
The capacitor voltage cannot change instantly. With 0 V across it, it acts as a short circuit at t=0+, and the charging current is limited only by the resistor.
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