Electricity Flashcards
Basic atom structure
Electrons outside- negatively charged Protons and neutrons- inside nucleus Protons-positively charged Neutrons- no charge
Atoms are electrically _ _ _ _ _ _ _ and ions are not _ _ _ _ _ _ _
Neutral
charged
Electricity and electrons
Electricity- flow of electrical charges
electrons- (negative charge) flow in the wires of a working circuit
How do electrons in a circuit move?
Electrons in a circuit move from the negative terminal to the positivite one
Good conductors and good insulators
Conductors- allow electricity charges to flow through them
eg) copper, iron, water
insulators- don’t not allow electricity charges to flow through them
eg) wood, plastic, rubber
metals are good conductors non metals are insulators
How can insulating materials be made to have a static charge?
Static electricity is the build up of electrical charges that are not moving. This build-up is the result of friction or rubbing one material against another.
can only build up in an insulating material
can be useful or a problem
can be discharged, often with a spark
eg) when polythene is rubbed with a woollen cloth, the polythene pulls electrons from the wool
Uses and problems accociated with static electricity
uses- air fresheners, photocopying, spray painting, getting lint off clothes, picking up small light weight things
problems- lightning, catching on fire, electric shocks, dust and dirt attract to insulators
What is a circuit composed of?
A power supply, connecting wires, load
Common circuit symbols
Difference between series and parallel circuits
Current definition
A measure of how much electric charge flows through a circuit
current is measured in Amps with an ammeter
ammeter MUST be placed in a series circuit
Definition of AC DC
AC- alternating current (changes paths)
DC- direct current (just goes one way)
Voltage Definition
A measure of the potential difference in electrical charge between two parts of a circuit
voltage is measured in Volts with a voltmeter
voltmeter MUST be in a parallel circuit
