Frequently Asked Questions...
can't figure out this physics question?
The cell membrane in a nerve cell has a thickness of about 0.12 micrometers. Modeling the cell membrane as 2 parallel surfaces of charge, each with a charge density of 5.2x10^-6 Coulomb/m^2, find the magnitude of the electric field (in N/C) inside the membrane. Assume the membrane has a dielectric constant of k=7 (k=Kappa).
Answer:
think capacitance
C = kA/d
then
V = C/Q
elctric field is
V/d
where
Q = net charge
A = area (1m^2)
d = distance apart
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