Static Electricity
HyperPhysics

jenvan3.mov

 

Unit III Electricity & Magnetism

 

Static Electricity Intro

 

 

I.  Static Electricity - electronic charges flowing in no particular direction. (trapped in a body)

 

A) Electricity of the Atom

Atoms are
 ordinarily neutral

 

#p = #e-

 

n has no charge

 

p has +1 charge

 

e- has -1 charge

 

 

Charge electron
 

-1.6 x 10-19 Coulombs
(Reference)

 

 

 

 

 

Did you know ....

 

Benjamin Franklin 

National Portrait Gallery, London: NPG 327
Author - Joseph Siffred Duplessis (died 1802)

  • coined the terms positive and negative for electrical charge

  • proved lightning was static electricity

  • invented lightning rod

  • built a static electricity generator 

 
 

 

 

1. Atoms become charged by gaining or losing ...

 

 

Electrons

 

 

3 Big Rules of Electrostatics

Opposites Attract




Likes Repel



Only Electrons Move

(Protons move, but don't leave nucleus)


 

 

Charge plates can deflect an electron

 

 

 

 

Mg+2   F -1

Mg atom
Lost 2 electrons

 

F  atom
gained 1 electron

20 p , 18 e-
What's the charge?

 

 

+ 2

 

 

 

 

Why are protons never lost or gained?

 

Protons are held in the nucleus by the strongest forces in the universe

 

 

 

a) Ion: electrically charged particle:

 

 

Charge is unbalanced

 

 

 

 negative charge

 

 

 

#e > #p

 

 

 

 

 

positive charge

 

 

#p > #e

 

 

 

 

2. Charged objects lose their charge when grounded. (become neutral)

[ Flash ]

 

"What is the

bottom prong of

 a plug called?"

 

"The bottom prong of
a plug called the ground.
It discharges any excess
charge that may develop
in an electrical device"

 

When grounded:

 

 

Negatively charged objects ...

 

 

... lose electrons

and become neutral.

 

 

 

 

Positively charged object ...

 

 

... gain electrons

and to become neutral.

 

 

Electroscope

 

 

ŠTony Mangiacapre., - All Rights Reserved [Home]
Established 1995
Use any material on this site (w/ attribution)