The membrane of the axon of a nerve cell is a thin cylindrical shell of radius r = 10-5 m, length L = 0.14 m, and thickness d = 10-8 m. The membrane has a positive charge on one side and a negative charge on the other, and acts as a parallel-plate capacitor of area A = 2?rL and separation d. Its dielectric constant is about ? = 5.
(a) Find the capacitance of the membrane.
_____ nF
(b) If the potential difference across the membrane is 89 mV, find the charge on each side of the membrane.
_____ nC
(c) Find the electric field through the membrane.
______V/m