Question

The capacitive reactance at $1600Hz$ is $81\Omega$. When the frequency is doubled then capacitive reactance will be

• A. $40.5\Omega$
• B. $81\Omega$
• C. $162\Omega$
• D. $Zero$

Answer 1

Answer: (A)

$40.5\Omega$

capacitive reactance is inversely proportional to the frequency
$X_C=\frac{1}{2\pi fC}$
therefore when frequency is doubled capacitive reactance will get halved therefore new $X_C$ is $40.5\Omega$