Static Electric Charge (9-2)Static Electric Charge (9-2)
Static electric Static electric charge-charge- A charge on a A charge on a
substance that substance that stays in the same stays in the same placeplace
Examples of Static ChargeExamples of Static Charge
Lightning-Lightning-(9-10)(9-10)
http://www.youtube.com/watch?v=gKPwkau0Dh0&feature=related
http://www.youtube.com/watch?v=HLcFHo2HR7I&feature=related
Static cling-Static cling-
Producing Static ElectricityProducing Static Electricity
Charge by Friction-Charge by Friction- (9-3) (9-3) Electric charge is transferred by rubbing Electric charge is transferred by rubbing
object togetherobject together
Producing Static ElectricityProducing Static Electricity
We know which We know which object will cause object will cause which charge which charge when caused by when caused by friction using the friction using the Electrostatic Electrostatic SeriesSeries
(9-3)(9-3)
(Items above become (Items above become negatives) negatives)
Rubber Rubber Ebonite Ebonite Polyethylene Polyethylene cotton cotton silk silk wool wool glass glass acetate acetate fur/hair fur/hair (Items below become (Items below become
positives) positives)
Producing Static ElectricityProducing Static Electricity
Charge by conduction (contact)- (9-5)Charge by conduction (contact)- (9-5) Charge is transferred by touching a Charge is transferred by touching a
charged object to an uncharged objectcharged object to an uncharged object
http://www.shep.net/resources/curricular/physics/P30/Unit2/electroscope.swf
Producing Static ElectricityProducing Static Electricity
Charge by induction- (9-8)Charge by induction- (9-8) Neutral object becomes charged when a Neutral object becomes charged when a
charged object is brought near it.charged object is brought near it. Induced charge can become more Induced charge can become more
permanent if a ground wire is attached to it. permanent if a ground wire is attached to it.
http://www.shep.net/resources/curricular/physics/P30/Unit2/electroscope.swf
Laws of Electric Charge (9-Laws of Electric Charge (9-2)2)
Unlike charges attract one anotherUnlike charges attract one another Like charges repel one anotherLike charges repel one another
Removing Static Electricity Removing Static Electricity (9-7)(9-7)
Discharge (neutralize)-Discharge (neutralize)- When excess electric charge is removed When excess electric charge is removed
from an object.from an object. Discharge can be quick and explosive Discharge can be quick and explosive
(lightning)(lightning) Discharge can be unnoticed (fabric softener Discharge can be unnoticed (fabric softener
sheet)sheet)
http://www.youtube.com/watch?http://www.youtube.com/watch?v=R7cgazVkhTk&feature=related v=R7cgazVkhTk&feature=related
Removing Static ElectricityRemoving Static Electricity
GroundingGrounding Connecting the object to the earthConnecting the object to the earth
The charge is shared with the entire earthThe charge is shared with the entire earth
Discharge at a pointDischarge at a point Objects made into a point have Objects made into a point have
electrons pushed off the end.electrons pushed off the end.
Detecting Static ChargeDetecting Static Charge
ElectroscopeElectroscope -a device used to detect -a device used to detect the presence of charge. (9-4) the presence of charge. (9-4) usually constructed with a metal plate or usually constructed with a metal plate or
sphere at the top of a metal post with sphere at the top of a metal post with thin foil leaves hanging from the bottom thin foil leaves hanging from the bottom of the post of the post
http://www.regentsprep.org/Regents/http://www.regentsprep.org/Regents/physics/phys03/aeleclab/nerscope.htm physics/phys03/aeleclab/nerscope.htm
Dangers of Static ElectricityDangers of Static Electricity
Cause firesCause fires
http://www.metacafe.com/watch/862578/http://www.metacafe.com/watch/862578/static_electricity_causes_fire_at_gas_statiostatic_electricity_causes_fire_at_gas_station/ n/
Can wreck electronics (need grounding Can wreck electronics (need grounding wire)wire)
Can hurt (shock) or cause death (10-9)Can hurt (shock) or cause death (10-9)
http://www.youtube.com/watch?http://www.youtube.com/watch?v=CpxKEGdfDxI&feature=related v=CpxKEGdfDxI&feature=related
Uses of Static Electricity (9-Uses of Static Electricity (9-8)8)
Electrostatic air cleanersElectrostatic air cleaners Removes dust and other particles by the Removes dust and other particles by the
attraction of unlike chargesattraction of unlike charges Electrostatic spray paintingElectrostatic spray painting
The paint and the object to be painted The paint and the object to be painted are given opposite chargesare given opposite charges
http://video.google.com/videoplay?http://video.google.com/videoplay?docid=-860069260229630847 docid=-860069260229630847
Uses of Static Electricity (9-Uses of Static Electricity (9-11)11)
Fabric softener sheetsFabric softener sheets Allows electric charge to move in Allows electric charge to move in
between clothes instead of building up.between clothes instead of building up. PhotocopiersPhotocopiers Cell phones and car radios Cell phones and car radios