A typical cell has a membrane potential of -70 mV, meaning that the potential inside the cell is 70 mV less than the potential outside due to a layer of negative charge on the inner surface of the cell wall and a layer of positive charge on the outer surface. This effectively makes the cell wall a charged capacitor. Because a cell's diameter is much larger than the wall thickness, it is reasonable to ignore the curvature of the cell and think of it as a parallel- plate capacitor. Part A How much energy is stored in the electric field of a 50-um-diameter cell with a 7.0-nm-thick cell wall whose dielectric constant is 9.0? Express your answer to two significant figures and include the appropriate units. Uc= Submit I μA Value Request Answer Units ?

A typical cell has a membrane potential of -70 mV, meaning that the potential inside the cell is 70 mV less than the potential outside due to a layer of negative charge on the inner surface of the cell wall and a layer of positive charge on the outer surface. This effectively makes the cell wall a charged capacitor. Because a cell's diameter is much larger than the wall thickness, it is reasonable to ignore the curvature of the cell and think of it as a parallel- plate capacitor. Part A How much energy is stored in the electric field of a 50-um-diameter cell with a 7.0-nm-thick cell wall whose dielectric constant is 9.0? Express your answer to two significant figures and include the appropriate units. Uc= Submit I μA Value Request Answer Units ?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter26: Electric Potential

Section: Chapter Questions

Problem 48PQ: A particle with charge 1.60 1019 C enters midway between two charged plates, one positive and the...

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