Static electricity or electrostatics is a field of science and a class of phenomena involving the imbalanced charge present on an object, typically referring to charge with voltage of sufficient magnitude to produce a spark.

Generation

The presence of charge means that the objects will exhibit attractive or repulsive forces. Static electricity can also be generated by touching two objects together and then separating them, because of contact electrification and the triboelectric effect. Friction between two objects generates a great amount of static electric effects because of the many instances of contact and separation. Usually, substances that don't conduct electricity (insulators) are good at holding a surface charge. Some examples of these substances are rubber, plastic, glass, and pith. The charge that is transferred in static electricity is stored on the surface of each object. Static electric generators, devices which produce very high voltage at very low current, are used for classroom physics demonstrations.

Note that the presence of electric current does not detract from the electrostatic forces nor from the sparking, the corona discharge, or other phenomena. In other words, electric current is not the opposite of static electricity, and both phenomena can exist together at the same time.

Natural electrostatic phenomena are most familiar as an occasional annoyance in seasons of low humidity, but can be destructive and harmful in some situations (e.g. electronics manufacturing.) When working in direct contact with integrated circuit electronics (especially delicate MOSFETs), or in the presence of flammable gas, care must be taken to avoid accumulating and discharging a static charge.

See also

Electronics

• Wimshurst machine
• Van de Graaff generator
• First photoconductive copy
• List of electronics topics

Natural

• Triboelectric effect
• Bioelectricity
• Pith
• Cumulonimbus clouds (and Relative humidity)
  • Lightning
• Chemical Solutions
• Examples of electrical phenomena

Historical

• Luigi Galvani
• Pseudodoxia Epidemica

Other

• Cartridge (weaponry)
• Static

External links

• Humans and sparks, causes and cures (http://amasci.com/emotor/zapped.html)

ja:静電気