A parallel-plate vacuum capacitor has 7.22 J of energy stored in it. The separation between the plates is 2.30 mm. Part A If the separation is decreased to 1.45 mm, what is the energy now stored if the capacitor was disconnected from the potential source before the separation of the plates was changed? Express your answer in joules. U = 4.55 J Submit Previous Answers Correct INEED HELP ABOUT PART B Part B If the separation is decreased to 1.45 mm, what is the energy now stored if the capacitor remained connected to the potential source while the separation of the plates was changed? Express your answer in joules. ? U = 14.44 J Submit Previous Answers Request Answer X Incorrect; Try Again; 5 attempts remaining

A parallel-plate vacuum capacitor has 7.22 J of energy stored in it. The separation between the plates is 2.30 mm. Part A If the separation is decreased to 1.45 mm, what is the energy now stored if the capacitor was disconnected from the potential source before the separation of the plates was changed? Express your answer in joules. U = 4.55 J Submit Previous Answers Correct INEED HELP ABOUT PART B Part B If the separation is decreased to 1.45 mm, what is the energy now stored if the capacitor remained connected to the potential source while the separation of the plates was changed? Express your answer in joules. ? U = 14.44 J Submit Previous Answers Request Answer X Incorrect; Try Again; 5 attempts remaining

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter8: Capacitance

Section: Chapter Questions

Problem 49P: Suppose that the capacitance of a variable capacitor can be manually changed from 100 pF to 800 pF...

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