Static electricity Flashcards
Unit of electric charge
The coulomb (C)
Insulator
Any substance through which electric charge cannot flow
E.g. glass,perspex
Conductor
Any substance through which electric charge can flow
E.g. Metals
Where does static charge on a conductor tend to accumulate
where the conductor is most pointed
Where does static charge reside on a conductor?
the outside of it
Coulombs law
Coulomb’s law states that the electrical force between two charged objects is directly proportional to the product of the quantity of charge on the objects.
Electric field
Any region of space where a static electric charge experiences a force other than the force of gravity
It is always caused by other static charges in the vicinity
Line of force (Electric field line)
A line drawn in an electric field showing the direction of the force on a positive charge placed in the field
Electric field strength (E)
The force per coulomb
Uses of a gold leaf electroscope
detect charge
Indicate the approximate size of a charge
Test wether a charge is + or -
Explain how point discharge occurs.
charge accumulates at a point
air is ionised around the point / like charges are repelled / unlike charges are attracted
Define the term electric field intensity,
The intensity of the electric field is the force it can exert upon one unit of a positively charged particle placed inside the electric field
Explain how a lightning conductor works.
point discharge
transfers charge to ground
A battery is a source of emf. Name two other sources of emf.
mains, solar cell, thermocouple
Explain why a balloon that has been rubbed vigorously on a woolly jumper
can stick to a wall.
balloon becomes charged
sticks to opposite charges in the wall
