The potential difference across a cell membrane from outside to inside is initially at -90 mV (when in its resting phase). When a stimulus is applied, Na+ ions are allowed to move into the cell such that the potential changes to +20mV for a short amount of time.
(a) If the membrane capacitance per unit area is 1 uF/cm^2, how much charge moves through a membrane of area 0.05 cm^2?
(b) The charge on Na+ is e+. How many ions move through the membrane?