P3- Electricty Flashcards
define static electricty
The build up of charge in insulating materials
what happens when static electricty is dischared
sparks are produced
Do all objects have charge?
Yes but most object cancel out as they have an even amount of negitve and positve cancel each other out
What happnes when two insulating objects are rubbed together
The friction causes electrons to be rubbed off onto the other one
What happnens when two conducting materials are rubbed together
The charge lost travels back into the orginal object
can static electricity be built up in conducting materials
No it cant
What sub atomic particles are transfered when friction is created
Only electrons are transfered
What happens when the negtive charge builds up on an insultating object
A potenial difference is created between the negtively cahrged obejct and the earth (or any other earthed object)
What is the charge of an earthed object
0Volts
What happens when the potential difference between an earthed object and an insulator becomes large
Electrons ‘jump’ between the gap which create sparks
Can charge build up on conducting materials
Sometimes- although it is uncomen
What is an example of charge building up on a conducting material
A car creating friction between the wind as it drives
Do all charged obeject have an electrical field
Yes
Which way do elecrical field lines point
Positve to negitive
(positive point outwards, negitive point inwards)
How must electrical field lines be drawn
At a right angle to the surface
Where is a electrical field strongest
Clostest to the object
Where is the electrical field weaker
furhter away from the object
What happens when charged particles become closer
electrical fields
There electrical fields become stonger
What is the name of the force that attracts two particles together
Electrostatic force (or attraction)
Is air an insulator or a conductor
Its an electriacal insulator
What happens when air comes into contact with a strongly charged object
The air ionises(loses electrons) which causes the air to become a conductor and allows electrons to travel through as sparks
Define Coulomb
The unit of charge.
Diode
A component that only allows current to flow through in the forward direction. They
have very large resistances in the reverse direction.
Electric Current
The rate of flow of electrical charge. Its value is the same at any position in
a single closed loop. In metals, the charges that flow are electrons.
