Electric Current

n stream of electrically charged particles passing through a given area

(Movement of electrons in a wire)

A) Conductivity of Solids

1) Metals - contain many __________ electrons (good conductors)

2) Glass, fused quartz, rubber - good _________________

n Few free electrons

Insulators have a High _______________ - (Structural resistance to electrons flow)

3) Semiconductor - a material with a resistance _________________

_________________________________________________________

B) Conductivity of Liquids

1) pure liquids ______________________

2) liquid with dissolved ________________ conduct

( ___________________________________ solution)

( ion movement transfers charge not electrons)

C) Conductivity of Gases

n Gases conduct 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 ________________________________________________/

plasma – very hot ionized gas

D) Conditions for passing current

1) complete circuit

2) ______________________________ (voltage) supplied by some source

ex. Battery generator

3) conductor