P2-Electricity Flashcards
What is current
The rate of flow of the electric charge or flow of charge per second
What is current measured in
Ampere(A)
What is potential difference
How much energy is transferred to a component
potential difference is measured in?
Volts(V)
Potential difference
Energy Transferred/Charge
Resistance is measured in?
Ohms
What factors affect resistance of a wire
Material of wire
Thickness of wire
Length of wire
Temperature of wire
What is ohms law
the current through a resistor at constant temperature is directly proportional
to the potential difference across the resistor
what happens when resistors are connected in series
The resistance is added
What happens when resistors are connected in parallel
The resistance is lower than any of the resistors
what is direct current
current that flows in one direction
what is alternating current
current which repeatedly reverses direction
What is the UK mains frequency
50 Hz
what are the three wires in a cable called
Live
Neutral
Earth
