Electrical and electronic components
Common standard electrical and electronic components and symbols are used in this course. These components can be used in circuits which perform functions, for example, switching a lamp on at night or switching a heater on when it becomes cold.
Common components
Cell
Provides electrical energy to charges in a circuit.
Battery
Provides electrical energy to charges in a circuit.
Diode
Allows current to flow through it in one direction only.
Resistor
Used in circuits to set current.
Variable resistor
Used to vary the size of current in a circuit.
Fuse
A fuse melts to break the circuit if the current is too large.
Some components are used to respond to some physical change in our surroundings, eg temperature rise (or fall), light level change. These devices are called Input devices.