Circuit Symbols

• Resistor - restricts or limits the flow of electrical current.

  
• LDR - the resistance depends on light intensity, as light intensity increases, resistance decreases.

  
• Thermistor - the resistance is dependant on temperature, as the temperature increases, the resistance decreases.

  
• Variable resistor - moving the position of the slider on the resistor changes the resistance.

  
• Diode - allows current to flow in one direction only, has a high resistance in the other direction.