Circuit Components
- The diagram below shows the circuit symbols that could be used in circuit diagrams
- You will be expected to know what each component is and how it behaves in a circuit
Circuit Symbols
Common circuit symbols used in circuit diagrams
Power supplies
- Cells, batteries, power supplies and generators all supply current to the circuit
Resistors
- Potential dividers, fixed and variable resistors, thermistors and light-dependent resistors (LDRs) are all used to control current
Meters
- Ammeters and voltmeters are used to measure the current and potential difference
- Ammeters are always connected in series whilst voltmeters are always connected in parallel
Electromagnetic Components
- Magnetising coils, relays and transformers use electromagnetic effects
- Relays use a small current in one circuit to switch on a much larger current in another
- Transformers 'step up' and 'step down' current and potential difference
Fuses
- Protect expensive components from current surges and act as a safety measure against fire