P2 - Circuits Flashcards
What does an ammeter do?
Measures the current through a component.
How must an ammeter be placed?
In series.
Rules about placing ammeters in circuits [2].
1) can be put anywhere in series.
2) never in parallel.
What do voltmeters do?
Measure the PD across a component.
Rules about placing a voltmeter [2].
1) must be placed in parallel around the component.
2) not placed around variable resistor or battery.
What is the standard test circuit used for? [2].
1) testing components.
2) getting V-I graphs.
What components are in the standard test circuit? [4]
1) component.
2) ammeter.
3) voltmeter.
4) variable resistor.
What happens as you vary a variable resistor? What does this allow you to do?
It alters the current flowing through the circuit.
You can take several pairs of readings from the ammeter & voltmeter to plot a graph.
How do you find the resistance of a component in a circuit?
Measure the current through & PD across the component.
