JEE Mains · Physics · STD 12 -7. Alternating current
An inductor of inductance \(2\,\mu\,H\) is connected in series with a resistance, a variable capacitor and an \(AC\) source of frequency \(7\,kHz\). The value of capacitance for which maximum current is drawn into the circuit is \(\frac{1}{x} F\), where the value of \(x\) is \(.........\). \(\left(\right.\) Take \(\left.\pi=\frac{22}{7}\right)\)
- A \(3875\)
- B \(3872\)
- C \(3800\)
- D \(3654\)
Answer & Solution
Correct Answer
(B) \(3872\)
Step-by-step Solution
Detailed explanation
\(\frac{1}{2 \pi fC }=2 \pi fL\) \(C =\frac{1}{4 \pi^2 f ^2 L }=\frac{1}{4 \times \pi^2 \times 49 \times 10^6 \times 2 \times 10^{-6}}\) \(C =\frac{1}{3872}\,F\) \(x =3872\)
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