Aparallel-plate capacitor in air has a plate separation d = 4 mm and square plates with area a = 25.0 cm^2. the plates are maintained to a constant potential difference of 255 v. determine the charge on the plates and the energy stored by the capacitor.

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.