p5. electricity and magnetism Flashcards
what is potential difference (P.D)measured in?
volts (V)
what is potential difference?
the energy used between 2 points in a circuit
which way does current flow?
(+) positive → (-) negative
which way does charge flow?
(-)negative → (+) positive
what is the equation for current (I) ?
I (current) = Q (charge) /T (time)
what is a conductor?
a substance or material that allows electricity to flow though it
what is a insulator?
a material or substance that does not allow the flow of electricity
what is a semi conductor
a material or substance that only conducts electricity when heated
what is a contact force ?
forces that only apply when there is contact eg. friction
what is a non-contact force ?
forces that apply when there is and isn’t contact eg. gravitational field, electric field
what is current ?
the flow of charge
what is resistance ?
the opposition of current flow in a electrical current.
what is the SI unit for potential difference ?
voltage/ volts (V)
what is the SI unit for charge?
coulombs (C)
What’s the equation for resistance ?
R = V / I
Resistance = voltage / charge
