Static electricity is an electrical charge at
rest. Static electricity is most commonly created by friction and separation. Friction
causes heat which excites the molecular particles of the material. When two materials
are then separated, a transfer of electrons from one material to the other may take
As electrons transfer, the absence or surplus
of electrons creates an electrical field known as static electricity. The simple
separation of two materials, as when tape is pulled off a roll, can also create
this same transfer of electrons between materials, generating static electrical
The amount of static electricity generated depends
upon the materials subjected to friction or separation, the amount of friction or
separation and the relative humidity of the environment. Common plastic generally
will create the greatest static charge. Low humidity conditions such as those created
when air is heated during the winter will also promote the generation of significant
static electrical charges.
Materials that easily transfer electrons (or
charge) between atoms are called conductors and are said to have "free" electrons.
Some examples of conductors are metals, carbon and the human body's sweat layer.
Materials that do not easily transfer electrons are called insulators. Some well
known insulators are common plastics, glass and air. Both conductors and insulators
may become "charged" with static electricity. When a conductor is charged, the free
electrons give it the ability to discharge rapidly when it comes close to another
conductor with a different potential.