P2 Electricity Flashcards
What is current?
The rate of flow of charge
What is potential difference?
The difference in electric potential between two points
What is resistance?
The opposition to the flow of current
How does a light dependent resistor work?
As light gets brighter, resistance decreases
How does a thermistor work?
As the temperature increases, resistance decreases
What happens to potential difference in a series circuit?
It is shared
What happens to current in a series circuit?
It is the same everywhere
What happens to potential difference in a parallel circuit?
It is the same across all components
What happens to the current in a parallel circuit?
It is shared
What happens if you add a resistor in parallel?
The total resistance decreases as there are more directions for the current to flow through
What is the voltage of UK mains supply?
230V
What is the frequency of UK mains supply?
50Hz
What colour is the neutral wire?
Blue
What is the neutral wire for?
It completes the circuit (0V)
What colour is the live wire?
Brown
What is the live wire for?
Provides the alternating potential difference (230V)
What colour is the earth wire?
Green and yellow
What is the earth wire for?
It provides a low resistance path to the earth if the circuit shorted
What is power?
The amount of energy transferred per second
What is a step-up transformer?
A transformer that is used to increase the voltage by having more turns on the secondary coil
What is a step-down transformer?
A transformer that is used to decrease the voltage by having more turns on the primary coil
How do you build up static electricity?
Use friction to rub two objects together, transferring electrons from one material onto the other
What happens when you have too much static electricity?
The potential difference is too large so electrons jump between the object and earth, creating a spark
What happens if you place a charged object in an electric field?
It experiences a force
