A capacitor with a capacitance of 100 F is charged to a potential difference of 24 V . After disconnecting the charging battery, the capacitor is connected to a different battery of emf 12 V such that the positive plate of the capacitor is attached to the positive terminal of the battery. Determine the charges on the capacitor before and after the reconnection.

Step-by-step solution

The initial charge on the capacitor is given by Q_ i = C V₁ . Substituting the given values, Q_ i = 100 F 24 V = 2400 C . When the capacitor is connected to a new battery of emf 12 V , the potential difference across the capacitor in steady state becomes equal to the emf of the new battery. The final charge on the capacitor is given by Q_ f = C V₂ . Substituting the values, Q_ f = 100 F 12 V = 1200 C . The charges before and after reconnection are 2400 C and 1200 C respectively.