The inner and outer surfaces of a cell membrane carry a negative and a positive charge, respectively. because of these charges, a potential difference of about 0.076 v exists across the membrane. the thickness of the cell membrane is 7.30 10-9 m.
what is the magnitude of the electric field in the membrane?

Air conditioners not only cool air, but dry it as well. suppose that a room in a home measures 5.0m×9.0m×2.4m . if the outdoor temperature is 30 ∘c and the vapor pressure of water in the air is 85 % of the vapor pressure of water at this temperature, what mass of water must be removed from the air each time the volume of air in the room is cycled through the air conditioner? the vapor pressure for water at 30 ∘c is 31.8 torr.