COMEDK · Physics · 23. Alternating Current
An ideal inductor is connected across a capacitor. Oscillations of energy K are set up in the circuit. The capacitor plates are slowly drawn apart such that the frequency of oscillations is quadrupled. The work done in the process is
- A zero
- B 2 K
- C 15 K
- D 13 K
Answer & Solution
Correct Answer
(C) 15 K
Step-by-step Solution
Detailed explanation
The energy stored in an LC circuit is \(K = \dfrac{1}{2} \dfrac{q^2}{C} = \dfrac{1}{2} LI^2\). The frequency of oscillation is \(f = \dfrac{1}{2\pi \sqrt{LC}}\). Given that the frequency is quadrupled, \(f' = 4f\). Since \(L\) is constant,…
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