The capacitive reactance of a capacitor in a D.C. circuit is
Correct answer: D. ∞
- A. 0
- B. ω⋅C
- C. 1/ω⋅C1
- D. ∞
Explanation
Explanation: In a DC (direct current) circuit, the frequency ω is considered to be 0, because DC does not vary with time. The capacitive reactance (XC ) of a capacitor is given by the formula XC =1/ ω⋅C . Since ω is 0 for a DC circuit, the capacitive reactance (XC ) becomes infinite.
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Alternating current varies periodically, so phase relationships become essential when current passes through a resistor, capacitor or inductor. The chapter distinguishes resistance from capacitive and inductive reactance, explains phase lead and lag, and connects changing electric and magnetic fields with the production and properties of electromagnetic waves.
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