Nuture of Electricity

        It was known since the ancient Greeks that when a piece of amber or glass is rubbed with silk or fur , it achieves the power of attracting light objects . Later on , this phenomenon was studied and world "electric" (after Greek "electron" - "amber" ) was put in use . During the 18-19th centuries many discoveries about the nature of electricity were made : Charles Coulomb investigated the forces between the charged objects ; Benjamin Franklin invented the lighting rod , etc.
      There was developed the idea that there are two kinds of electricity , which were called resionous electricity , andther opposite kinds of electricity attract one another , where as similar kinds repel one another.
      The study of electricity may be divided into three classes (or branches) :
- magnetism
- electrostatics
- electrodynamics

      Magnetism is the property of the molecules of iron and other certain sudstances due to which they store energy in a field because of the arranged movement of the electrons intheir atoms .
      Electrostatics is the study of electricity at rest , or static electricity . Examples of type of electricity are charges on condenser plates .Rubbing glass with silk produces static electricity .

     Electrodynamics is the study of electricity in motion , or dynamic electricity . The electricity which flows through wires for ligth and power purposes is a good example of the latter type of electricity .