4. A parallel plate capacitor has a capacitance of 349 nF, and a potential difference of 56 V between the plates. The charging battery is disconnected and a paraffin slab (k = 2.2) is %3D inserted between the plates. (a) What is the potential energy of the device before and after the insertion of the slab? (b) What is the potential energy of the device before and after, if the inserted slab is a porcelain slab (k = 6)? %3D

4. A parallel plate capacitor has a capacitance of 349 nF, and a potential difference of 56 V between the plates. The charging battery is disconnected and a paraffin slab (k = 2.2) is %3D inserted between the plates. (a) What is the potential energy of the device before and after the insertion of the slab? (b) What is the potential energy of the device before and after, if the inserted slab is a porcelain slab (k = 6)? %3D

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter20: Electric Potential And Capacitance

Section: Chapter Questions

Problem 55P

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