Electric Current
- stream of electrically charged particles passing through a given area (movement of electrons in a wire
A) Conductivity of Solids
1) Metals - contain
many free electrons (good conductors)
2) Glass, fused quartz, rubber - good insulator
Few free electrons
Insulators have a High Resistivity
(Structural resistance to electrons flow)
3) Semiconductor - a material with a resistance between conductor and an insulator
B) Conductivity of Liquids
1) pure liquids don’t conduct
2) liquid with dissolved ions conduct
(electrolyte solution)
(ion movement transfers charge not electrons)
C) Conductivity of Gases
Gases conduct when ionized (charged) when exposed to:
a) high energy radiation
b) OR electric field
c) OR with collision with high speed particles
Charge in a gas is transferred by ions and electrons
Plasma–very hot ionized gas
4th state of matter
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