Static Electricity Flashcards
how do insulating materials become charged.
When they rub against each other, negatively charged electrons rub off one material and onto the other.
what needs to happen for the material to become negatively or positively charged?
negative charge = gain of electrons
positive charge = loss of electrons
what happends when two electrically charged objects are brought close together.
They exert a force on each other.
what happens when two objects that carry the same type of charge are brought together
they will repel
what happens when two objects that carry a different type of charge are brought together
they will attract
what type of force is attraction and replulsion?
non contact force / electrostatic
what needs to happen to increase the potential difference between the object and the earth?
the charge of the isolated object needs to increase
what would happen when the potential difference between the object and the earth becomes high enough?
a spark may jump across the gap between the object and any earthed conductor brought near it
do charged objects create electric fields around them?
yes
where is an electric field the strongest
closest to a charged object
what happens to the field when it gets further away from the charged object
the field gets weaker
what happens when a second charged object is placed in a field
the object experiences a force. The force gets stronger as the distance between the objects decrease.
how is static electricity created
When we rub two surfaces together, we produce static electricity. This occurs when electrons move from one surface to the other. We get a build up of static positive charge on one surface, and an equal static negative charge on the other surface.
how does sparking occur
the charge difference between the earth and charged surface gets so big that electrons will jump from the charged surface to the earth. As the electrons jump, we will be able to see a spark.
how is a charged difference created in static electricity
As charge builds up on a surface, we start to create a difference in charge between the charged surface and the earth. Usually, the earth is at zero volts. As we charge the surface, the difference in charge between the surface and the earth will get bigger and bigger.
what does the triboelectric series do
it lists materials in an order of whether they are more or less likely to lose/gain electrons.
how do electrons move in a conductor
they are free to move around, move easily through material
what is charging by induction induction
when a charged insulator is brought close to an uncharged conductor, it will cause the conductor to be charged by induction
where do electrons remain in an insulator
near the surface
how is charge distributed in a conductor
evenly
what is earthing
connecting a charged body to the earth via a conductor
how can we avoid large build ups of charge which are very dangerous
earthing
what is a static charge
an electrical charge that remains at rest on an object, rather than flowing through a conductor. It is caused by the transfer or redistribution of electrons on the surface of a material.
what is a field
a regiod on influence. (A region where a force can act on an object)
what do gravitational fields act on
masses
what do electric fields act on
charges
what do electrical field lines indicate
the direction of field
what is the only way to produce electrostatic charges
movement of electrons
effects of static charge
Static charges can have several effects, including attraction and repulsion, sparks, and electrical shock. They can also affect sensitive electronic equipment, causing damage or interference.
how can electrical fields generate static charges
Electric fields can generate static charges by inducing a charge separation on a material by exposing the material to an electric field, causing electrons to rearrange on the surface of the material and generate a static charge.
electrostatic charge in spray painting
A positively charged electron within the spray nozzle charges the paint particles. Because these particles all have a positive charge, they repel each other and break apart, resulting in a fine mist that coats evenly.
static electricity in inkjet printers
in printers, there are 2 charged plates with ink drops fired between them and deflected to the right position on a page
how do electrostatic precipitators clean dust and smoke from industrial plants
dust particles are given a negative charge so they stick to positive metal plates for removal
danger of static electricity to planes
when planes fly they become charged. these charges can escape to the earth and cause sparks when refuelling. important to earth the plane
what happens when you earth an object.
When you earth it, electrons can flow through the path to or from the object. This means the amount of electrons in the object will return to normal and the object will lose its charge.
how can dust build ups happen to screens.
screens can become charged, so they attract light uncharged particles such as dust.
why can you get a small spark or shock when you take off clothes
charges can build up on clothes
