Forest EngPhys Chapt21

Triboelectricity (a.k.a. static electricity)

When an initially neutrally charged person walks across the wool carpet, the loosly bound electrons in his leather shoes can be taken by the atoms in a wool carpet. The person becomes more positively charged with each step taken.

When the positively charged person nears a metal (conducting) door, they will attract negative charge. The charge moves from the door to the positively charged person.

If the air gap is small enough the charge could even "jump" between the door and the person, a spark discharge.

Notice that only the negative charge moved in the conducting metal door.

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