MCQ
The capacitor offers zero resistance to.
- AD.C. only
- BA.C. & D.C.
- CA.C. only
- Dneither A.C. nor D.C.
✓
Answer
- A.C. only
Explanation:
Capacitive reactance is given as
$\text{X}_\text{C}=\frac{1}{\omega\text{C}}$From this relation we can see that the value of capacitive reactance and therefore its overall impedance (in Ohms) decreases to zero as the frequency increases acting like a short
circuit. Likewise, as the frequency approaches zero or DC, the capacitors reactance increases to infinity, acting like an open circuit which is why capacitors block DC.
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