Consider a portion of a cell membrane that has a thickness of 7.50 nm and 1.8 pm x 1.8 pm in area. A measurement of the potential difference across the inner and outer surfaces of the membrane gives a reading of 91.5 mv. The resistivity of the membrane material is 1.30 x 107n - m. (a) Determine the amount of current that flows through this portion of the membrane. (b) By what factor does the current change if the side dimensions of the membrane portion is halved? The other values do not change. O increase by a factor of 4 O decrease by a factor of 4 O increase by a factor of 2 O decrease by a factor of 8 O decrease by a factor of 2

Consider a portion of a cell membrane that has a thickness of 7.50 nm and 1.8 pm x 1.8 pm in area. A measurement of the potential difference across the inner and outer surfaces of the membrane gives a reading of 91.5 mv. The resistivity of the membrane material is 1.30 x 107n - m. (a) Determine the amount of current that flows through this portion of the membrane. (b) By what factor does the current change if the side dimensions of the membrane portion is halved? The other values do not change. O increase by a factor of 4 O decrease by a factor of 4 O increase by a factor of 2 O decrease by a factor of 8 O decrease by a factor of 2

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter28: Current And Resistance

Section: Chapter Questions

Problem 68PQ

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