A parallel-plate air capacitor of capacitance C0 is connected to a cell of emf ℰ and then disconnected from it. A dielectric slab of dielectric constant K, which can just fill the air gap of the capacitor, is now inserted in it. (a) The potential difference between the plates decreases K times. (b) The energy stored in the capacitor decreases K times. (c) The change in energy is 1/2 C0ℰ2(K - 1).(d) The change in energy is 1/2 C0ℰ2(1 - 1/K)

A parallel-plate air capacitor of capacitance C0 is connected to a cel

1.	A parallel-plate air capacitor of capacitance C0 is connected to a cell of emf ℰ and then disconnected from it. A dielectric slab of dielectric constant K, which can just fill the air gap of the capacitor, is now inserted in it. (a) The potential difference between the plates decreases K times. (b) The energy stored in the capacitor decreases K times. (c) The change in energy is 1/2 C0ℰ2(K - 1).(d) The change in energy is 1/2 C0ℰ2(1 - 1/K)
Answer» Correct Answer is: (a, b, & d)

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