JEE Mains · Physics · STD 12 - 2. Electric potential and capacitance
A parallel plate air capacitor is connected to a battery. The plates are pulled apart at uniform speed \(v\). If \(x\) is the separation between the plates at any instant, then the time rate of change of electrostatic energy of the capacitor is proportional to \(x^\alpha\), where \(\alpha\) is _____.
- A \(-2\)
- B \(1\)
- C \(-1\)
- D \(2\)
Answer & Solution
Correct Answer
(A) \(-2\)
Step-by-step Solution
Detailed explanation
The electrostatic energy of a parallel plate capacitor is given by \(U = \dfrac{1}{2} C V^2\). For a parallel plate capacitor, the capacitance is \(C = \dfrac{\varepsilon_0 A}{x}\), where \(x\) is the separation between the plates. Since the capacitor remains connected to the…
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