A capacitor consists of two parallel metal plates in air. The distance between the plates is 5.00 mm and the capacitance is 72 pF. The potential difference between the plates is raised to 12.0 V with a battery. (a.) Calculate the energy stored in the capacitor. (b.) The battery is then disconnected from the capacitor; the capacitor retains its charge. Calculate the energy stored in the capacitor if the distance between the plates is now increased to 10.00 mm. The answers to (a) and (b) are different. Why is this so? Use your answers to estimate the average force of attraction between the plates while the separation is being increased.

A capacitor consists of two parallel metal plates in air. The distance between the plates is 5.00 mm and the capacitance is 72 pF. The potential difference between the plates is raised to 12.0 V with a battery. (a.) Calculate the energy stored in the capacitor. (b.) The battery is then disconnected from the capacitor; the capacitor retains its charge. Calculate the energy stored in the capacitor if the distance between the plates is now increased to 10.00 mm. The answers to (a) and (b) are different. Why is this so? Use your answers to estimate the average force of attraction between the plates while the separation is being increased.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter19: Capacitors

Section: Chapter Questions

Problem 3PA: You find that a 25-F capacitor connected to 480 VAC is defective. The storeroom has no capacitors...

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