Coulomb’s Law describes the electric force acting at a distance between charged objects that depends on the product of the charges of each object and the square of the distance between them. Coulomb’s Law is an inverse square law; the electric force is inversely proportional to the square of the distance between the charges. Because the electric force acts from a distance, a charged object has an electric field around it, similarly to the gravitational field around massive objects. The electric field also obeys an inverse square law. A charge interacts with the electric field and experiences a force. Objects in an electric field have potential energy due to their position in the field. If charged objects are released in the field, potential energy will be converted to kinetic energy. The potential energy per coulomb of charge is called electric potential and is measured in volts. The difference in electric potential between two locations is called voltage. All natural motion that does not require the addition of work moves a system toward less potential energy. Positive charges move from high to low potential, like mass moves from high to lower heights. Negative charges do the opposite and move from low to higher potential. There is no analog to this in a gravitational system because there is no negative mass.