4. An 8400 pF air-gap capacitor is charged by a power supply set to 9.1 V. It is removed from the power supply, and then a layer of mica (dielectric constant of 7) is inserted between the plates. a. What is the new capacitance of the plates? b. Consider just charge on the plates and the voltage across the plates. Which of them is the same before and after the mica is inserted? Why? c. Find the new value for the one that changed. d. Did the electric field increase, decrease, or stay the same when the mica was inserted? Explain how you know. e. Calculate the new potential energy stored by the capacitor. [5x10-8 J]

4. An 8400 pF air-gap capacitor is charged by a power supply set to 9.1 V. It is removed from the power supply, and then a layer of mica (dielectric constant of 7) is inserted between the plates. a. What is the new capacitance of the plates? b. Consider just charge on the plates and the voltage across the plates. Which of them is the same before and after the mica is inserted? Why? c. Find the new value for the one that changed. d. Did the electric field increase, decrease, or stay the same when the mica was inserted? Explain how you know. e. Calculate the new potential energy stored by the capacitor. [5x10-8 J]

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter8: Capacitance

Section: Chapter Questions

Problem 62P: When a 360-nF air capacitor is connected to a power supply, the energy stored in the capacitor is...

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