MCQ
An ac source is connected to a capacitor C. Due to increase in its operating frequency:
- ACapacitive reactance increases.
- BCapacitive current decreases.
- ✓Displacement current increases
- DDisplacement current decreases.
✓
Answer
Correct option: C.
Displacement current increases
(C)
Capacitive reactance $=\frac{1}{\omega C }= X _{ c }$ (say)
On increasing the operating frequency $w$ increases
As $X_c$ is inversily proportional to $w$ the value of $X_c$ decreses.
$\begin{array}{l}\therefore I_c=I_D \\
=\frac{V_o}{X_c}\end{array}$
As $X_c$ decreases therefore displacement current Id increases.
Capacitive reactance $=\frac{1}{\omega C }= X _{ c }$ (say)
On increasing the operating frequency $w$ increases
As $X_c$ is inversily proportional to $w$ the value of $X_c$ decreses.
$\begin{array}{l}\therefore I_c=I_D \\
=\frac{V_o}{X_c}\end{array}$
As $X_c$ decreases therefore displacement current Id increases.
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