Static Electricity

Textbook

questions:

SI units

electric conductors and insulators

protons and electrons

charges

movement of charges

+ve & -ve charges

electrostatic attraction

electrostatic discharge

electrostatic charging

bolded parts

What are electric charges?

matter is made up of tiny particles called atoms, atoms are also made of particles

How do +ve and -ve charges interact?

like charges repel, unlike attract

Measuring electric charge

measured in Coulombs (C), charge carried by proton/electron is 1.6x10^-19

measured using a coulombmeter

electric insulators vs conductors?

classified by their properties

electrostatic charging?

the study of static electric charges

electrical insulators do not conduct electricity, and are charged by friction

charging conductors by induction?

process of charging the conductor without contact between charger and conductor.

charged by induction not friction. (mobile electrons transferred to and away from conductors)

charging a single metal conductor by induction?

-ve charged rod can be used for induction. Electrons will flow out to the ground during earthing. Makes the conductor +ve charged

discharging a charged conductor?

done by earthing as electrons are free to move in conductors. (-ve and +ve charges become equal)

representing electric fields?

illustrated with lines and arrowheads. Shows the behavior of a small +ve charge if it were free to move in the electric field along the lines

lightning?

an atmospheric discharge of electrostatic charges that usually happens during thunderstorms
(reason why buildings have lightning conductors installed)

electrostatic discharge?

electric charges can pile up on trucks cuz of friction btw roads and tyres (antistatic materials have a thin layer of metallised film; acts as a electrostatic shield for equipment placed inside

photocopiers?

uses static electricity to produce printed documents. (laser printers also use a similar process)

electrostatic precipitators?

when fossil fuels are burned in power stations to generate electricity, they produce waste gases and fly ash. (fly ash is concerning as it pollutes env)

spray painting?

principles of electrostatic applied to spray paint vehicles. charged paint particles attracted to metal car body (earthed)