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Two identical capacitors, each of capacitance C, are charged to potentials V and 2V respectively, then connected in parallel with like plates joined. The common potential after sharing is
A{'text': 'V', 'label': 'A'}
B{'text': '2 V', 'label': 'B'}
C{'text': '1.5 V', 'label': 'C'}
D{'text': '3 V', 'label': 'D'}
Answer & Solution
Correct answer: C. {'text': '1.5 V', 'label': 'C'}
1. Initial charges: Q₁ = CV, Q₂ = C(2V); total Q = 3CV.
2. After connection (parallel, like plates) total capacitance = 2C.
3. Common V' = total charge / total cap = 3CV / 2C = 1.5 V.
4. Energy after < energy before — energy is dissipated as heat / radiation during the redistribution.
_Source: NCERT Class 12 Physics Part I, Ch 2 §2.15 derivation_
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