1ev is an energy unit equal to 1.6 x 10 -19 joules Gravitational potential energy increases as height increases. Kinetic energy changes only if velocity changes. Adding a resistor in parallel decreases the total resistance of a circuit. Adding a resistor in series increases the total resistance of a circuit. If two charged spheres touch each other add the charges and divide by two to find the final charge on each sphere.
Insulators contain no free electrons.
Ionized gases conduct electric current using positive ions, negative ions and electrons. Electric fields all point in the direction of the force on a positive test charge. Electric fields between two parallel plates are uniform in strength except at the edges. Millikan determined the charge on a single electron using his famous oil-drop experiment. All charge changes result from the movement of electrons not protons.