Electrified bodies are called those bodies which, when rubbed against another body, acquire the ability to exert force on light objects. Electrification is the process by which bodies become electrified. The instruments that detect whether a body is electrified are: a) the electric pendulum and b) the electroscope with movable leaves. Electric force is the force exerted between electrified bodies. The characteristics of electric force are as follows: a) it acts on different bodies than those on which magnetic force acts, b) it acts from a distance, and c) it is sometimes attractive and sometimes repulsive. To describe the electric interaction of two bodies, we accept that matter has a property which we associate with a physical scalar quantity called electric charge. Electric charge is denoted by the letter q or Q and has the unit 1 C (Coulomb).