A parallel-plate capacitor with a 0.1-mm air gap has a capacitance of 12 µF. (a) When this capacitor is connected to a battery, the maximum magnitude of charge on either plate is 0.18 mC (millicoulomb). What are the magnitude of the electric field between the plates and the energy density (energy per unit volume) in this region? (b) (c) Now suppose this capacitor is disconnected from the battery, and a slab of titanium dioxide (with dielectric constant 100) is inserted between the plates. Indicate whether each of the following quantities increases or decreases after insertion of the dielectric, as well as the factor by which each quantity changes: (i) potential difference across the plates; (ii) capacitance of the capacitor; and (iii) total energy stored in the capacitor. (No calculations are required here.) Calculate the total energy stored in the capacitor with dielectric described in part (b).

A parallel-plate capacitor with a 0.1-mm air gap has a capacitance of 12 µF. (a) When this capacitor is connected to a battery, the maximum magnitude of charge on either plate is 0.18 mC (millicoulomb). What are the magnitude of the electric field between the plates and the energy density (energy per unit volume) in this region? (b) (c) Now suppose this capacitor is disconnected from the battery, and a slab of titanium dioxide (with dielectric constant 100) is inserted between the plates. Indicate whether each of the following quantities increases or decreases after insertion of the dielectric, as well as the factor by which each quantity changes: (i) potential difference across the plates; (ii) capacitance of the capacitor; and (iii) total energy stored in the capacitor. (No calculations are required here.) Calculate the total energy stored in the capacitor with dielectric described in part (b).

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter16: Electrical Energy And Capacitance

Section: Chapter Questions

Problem 5CQ: A parallel-plate capacitor with capacitance C0 stores charge of magnitude Q0 on plates of area A0...

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