Components

• What do we need to know to draw circuit diagrams?

  The functions and symbols of components
• What is the purpose of a cell or battery in a circuit?

  To provide electric power to the circuit
• What does a switch do in a circuit?

  Controls the flow of electricity
• What happens when a switch is closed?

  Electricity flows through the circuit
• What is a filament lamp?

  A small bulb used in circuits
• What is the function of a fuse in a circuit?

  Breaks if too much current flows
• What is a diode?

  A component allowing current in one direction
• What is a light emitting diode (LED)?

  A diode that emits light when current flows
• Where are LEDs commonly used?

  In alarm clocks and traffic lights
• What is the function of an ammeter?

  Measures current in a circuit
• How is an ammeter connected in a circuit?

  In series with the circuit
• What does a voltmeter measure?

  Potential difference in a circuit
• How is a voltmeter connected in a circuit?

  In parallel with the circuit
• What are resistors used for in a circuit?

  To provide resistance to current flow
• What are the two types of basic resistors?

  Fixed and variable resistors
• What is a light dependent resistor (LDR)?

  A resistor whose resistance depends on light intensity
• How does an LDR behave in bright light?

  It has low resistance allowing high current flow
• What happens to an LDR's resistance in darkness?

  Resistance is high, limiting current flow
• How can LDRs be used in automatic night lights?

  They detect light and adjust resistance
• What is a thermistor?

  A resistor whose resistance depends on temperature
• How does temperature affect a thermistor's resistance?

  Higher temperatures lower resistance
• Where can thermistors be used?

  In car engines and electronic thermostats
• What are the main components and their functions in a circuit?

  • Cell/Battery: Provides electric power
  • Switch: Controls electricity flow
  • Filament Lamp: Acts as a small bulb
  • Fuse: Breaks circuit if current is too high
  • Diode: Allows current in one direction
  • LED: Emits light when current flows
  • Ammeter: Measures current in series
  • Voltmeter: Measures potential difference in parallel
  • Resistors: Provide resistance to current flow
• What are the types of resistors and their characteristics?

  • Fixed Resistors: Provide a set resistance
  • Variable Resistors: Allow modification of resistance
  • LDR: Resistance depends on light intensity
  • Thermistor: Resistance depends on temperature
• How do LDRs and thermistors function in practical applications?

  • LDRs: Used in automatic night lights and burglar alarms
  • Thermistors: Used in car engines and electronic thermostats