Static ElectricityStatic ElectricityStatic Electricity

abundance of positive or negative charge in an object

+

+

+

+

++

+

+

+

+- --

--

-

- --

-

+

+

+

+++- -

-

--

-

- --

-

+

+

++

Loosely held electrons (valence electrons) are able to move between objects and within materials

StaticStatic Electricity Electricity

The movement The movement of electronsof electrons

Where does the Where does the charge come from?charge come from?

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Charging materials by frictionCharging materials by friction

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++++

++

-- -- -

-

-Acetate

loses negative charge

= Positive

Cloth gains negative charge

= Negative

Acetate rod Cloth

Two materials can become electrically charged when they are rubbed against each other.

Static ElectricityStatic Electricity

+++++

++

+

++

Repel and AttractRepel and Attract---- -

--

-- ----- -

--

-- ----- -

--

-- -Two materials which have different charges will attract each other.

Two materials which have the same charge will repel each other.

When a material which is charged comes near something which isn’t charged, it tends to induce a charge. This is because the electrons in the uncharged substance move away from the charged object.

---- -

--

-- -+

++

++++

+++ +

+

--

-

-

---

-

--

-

CHARGING BY INDUCTIONCHARGING BY INDUCTION

ConductorsConductorsConductor

material that allows electrons to move through it easily

e- are loosely held ex: metals like copper and

silver

InsulatorsInsulatorsInsulator

material that doesn’t allow electrons to move through it easily

e- are tightly held ex: plastic, wood, rubber, glass

Static ElectricityStatic ElectricityStatic Discharge the movement of electrons

to relieve a separation in charge

Static ElectricityStatic ElectricityGrounding

Provides a path for electrons to travel to relieve a difference in charge