Fundamentals of Static Charge

Static charge buildup is a result of physically separating a poor conductor from a good conductor or another poor conductor. When different materials touch each other, the electrons move across the interface from one surface to the othpr. Upon separation, more of the electrons remain on one surface than on the other one material becomes positively charged and the other negatively charged. 

If both the materials are good conductors, the charge buildup as a result of separation is small because the electrons are able to scurry between the surfaces. If, however, one or both of the materials are insulators or poor conductors, electrons are not as mobile and are trapped on one of the surfaces, and the magnitude of the charge is much greater. 

Household examples that result in a buildup of a static charge are walking across a rug, placing different materials in a tumble dryer, removing a sweater, and combing hair. The clinging fabrics and sometimes audible sparks are the result of the buildup of static charge. 

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