MCQ
The capacitor offers zero resistance to.
- A$D.C$. only
- B$A.C.\ \&\ D.C.$
- ✓$A.C.$ only
- Dneither $A.C.$ nor $D.C.$
✓
Answer
Correct option: C.
$A.C.$ only
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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