P3.2 Simple circuits Flashcards
What do you need to make current flow in a circuit?
Potential Difference
What do you measure potential difference with?
A voltmeter
In a series circuit, what stays the same across the circuit?
Current
In a parallel circuit, what stays the same across the circuit?
P.T
How do you measure P.T in a series circuit?
P.T means electrical difference so you need to connect a voltmeter to both sides of a component
What do all the currents added up in a parallel circuit add up to?
Near the batteries current
How is resistance produced?
When electrons collide with the ions in the lattice
What does a variable resistor do?
adjust the value of current or voltage
What does the graph look like for a lamp?
like a S shape
Current decreases as P.T ____
Increases
What is a diode?
A component which only allows current to flow in one way
What does the graph look like for a diode?
Flat into a sudden increase in current
What is a thermistor?
They are at the end of digital thermometers and their resistance depends on the temperature
If the thermistor is put in something cold what happens to the resistance?
Increases
If the thermistor is put in something hot what happens to the resistance?
Decreases
What causes the resistance of an LDR to change?
Light intensity
As light intensity increases, the resistance ____
Decreases
If you have a series circuit and you add another lamp, what happens to the current and resistance?
Current decreases
Net resistance increases
If you have a parallel circuit and you add another lamp, what happens to the current and resistance?
total current increases
net resistance decreases
What is power measured in?
Watts
What is potential difference?
The amount of energy transferred by each stage
