An empty parallel plate capacitor is connected between the terminals of a 4.4-v battery and charged up. the capacitor is then disconnected from the battery, and the spacing between the capacitor plates is quadrupled. as a result of this change, what is the new voltage between the plates of the capacitor?
i have: e = v/de =9 vthen the distance is doubled 9(2) = 18 v

Electric field of the earth. the earth has a net electric charge that causes a field at points near its surface equal to 150 n> c and directed in toward the center of the earth. (a) what magnitude and sign of charge would a 60-kg human have to acquire to overcome his or her weight by the force exerted by the earth’s electric field? (b) what would be the force of repulsion between two people each with the charge calculated in part (a) and separated by a distance of 100 m? is use of the earth’s electric field a feasible means of flight? why or why not?