Key Circuit symbols Flashcards
What is wire made from?
A metallic conductor so current can easily pass from one part of the circuit to another
What happens when a switch is in the open position?
The circuit is broken so no current flows
What is the function of a closed switch?
The circuit is complete and current flows
What does a cell supply to the circuit?
Electrical energy
What is the positive terminal of a cell?
The larger terminal on the left is the positive (+) terminal
What is a battery?
More than one cell
What does a lamp convert electrical energy into?
Light
What is the purpose of a fuse?
A safety device which melts to break the circuit if the electrical current exceeds a specified value
What does a voltmeter measure?
Potential difference
What instrument is used to measure electrical current?
Ammeter
What does a resistor do?
Restricts the flow of electrical current
In what way can a resistor be used?
To limit the flow of current to a particular component
What is the function of a diode?
Allows current to flow in one direction only
What does a thermistor convert?
Heat to electrical resistance
What is the purpose of a variable resistor?
Used to control current
