static electricity Flashcards
how does static electricity occur
when electric charges are transferred onto, or off the surface of insulators
how do insulators become positively charged
when electrons move off the insulator and onto the cloth due to friction
how do insulators become negatively charged
when electrons move onto the insulator due to friction
what are 3 electrostatic behaviours seen in everyday life?
electric shocks
lightning strikes
electrostatic induction
what are electrostatic shocks?
electrons can be transferred onto your clothes by friction, and they stay on your clothes as they are insulators, however, if you touch a metal handle the electrons can conduct to earth and you will receive a shock
how do lightning strikes use electrostatic?
- ice particles in clouds gain electrons from other ice particles by friction
- the bottom of the cloud gains electrons and a negative charge
- electrons in the ground are repelled by the bottom of the cloud
- which causes the lightning to jump to the earth as a spark of electrons
what are lightning strikes an example of
electrostatic induction
what is an example of electrostatic induction?
when a charged object attracts an uncharged object. this happens because the charged object will induce a current in the uncharged object.
what are the 2 uses of electrostatics?
insecticide sprays
paint sprayers
how are electrostatics used in insecticide sprayers?
- the nozzle of the sprayer is connected to an electricity supply
- droplets get the same kind of static energy
- droplets repel each other so that the spray spreads evenly
how are electrostatics used in paint sprayers?
- the nozzle of the sprayer is connected to an electricity supply
- droplets get the same kind of static energy
- droplets repel each other so that the spray spreads evenly
- the object being painted is given the opposite charge so that the paint is attracted to the object, meaning less energy is wasted
what is the danger of electrostatic charges?
when vehicles move, the friction between the air and the vehicles causes electrons to be transferred and the vehicle becoming charged. friction between the fuel and the pipe it is flowing in can also cause the transfer of electrons, which could ignite the fuel
in which direction does the electric field of a positive point charge go
radially outwards
in which direction does the electric field of a negative point charge go
radially inwards
what is an electric field?
the area around a charged particle, that causes it to be affected by a non-contact force
