Constant & Variable Resistance
- Resistors come in two types:
- Fixed resistors
- Variable resistors
- Fixed resistors have a resistance that remains constant
- Variable resistors can change the resistance through the circuit
- This therefore can vary the amount of current through the circuit
- For fixed and variable resistors, once the resistance is set, it will stay at this value no matter how the current changes
- However, the resistance of components such as lamps, diodes (diodes and LEDs), thermistors and LDRs (light dependent resistors) changes with the current through the component
Fixed and variable resistor circuit symbols