Circuit Components and Their Symbols
Components are used in constructing electrical circuits.
Here’s every circuit symbol that can come up in your exams:
- OPEN SWITCH: Makes the circuit NOT complete and current cannot flow.
- CLOSED SWITCH: COMPLETES the circuit and allows current to pass.
- CELL: Indicates a single cell battery that provides the potential difference (voltage) needed for the current to flow.
- BATTERY: A combination of cells, supplying electricity to the circuit.
- LAMP: Illuminates when current passes through it.
- AMMETER: Used to MEASURE the CURRENT flowing through a circuit; it is always connected in SERIES.
- VOLTMETER: MEASURES the POTENTIAL DIFFERENCE (voltage) across a component and is connected in PARALLEL.
- RESISTOR: Indicates a component that opposes the flow of current, introducing RESISTANCE to the circuit.
- VARIABLE RESISTOR: A resistor whose RESISTANCE can be ADJUSTED. It is used to CONTROL CURRENT flow.
- THERMISTOR: A temperature-dependent resistor, meaning its RESISTANCE CHANGES with TEMPERATURE.
- LIGHT DEPENDENT RESISTOR (LDR): A resistor that CHANGES its RESISTANCE based on the LIGHT INTENSITY it's exposed to.
- DIODE: Allows CURRENT to flow in only ONE DIRECTION, ensuring components are protected from reverse current.
- LIGHT EMITTING DIODE (LED): Emits LIGHT when current flows through it and also allows current to flow in only ONE DIRECTION.
- FUSE: Acts as a SAFETY device that breaks the circuit if the CURRENT becomes too HIGH.