Electricity

• The current is the rate at which charge flows through an object.
• What are the two types of electrical current?

  Direct current and alternating current.
• What does a switch do in an electrical circuit?

  A switch turns a circuit on (closed) and off (open).
• How does a lamp function in an electrical circuit?

  It allows current to flow, heating the filament to emit light.
• What is a fixed resistor?

  A resistor that restricts the flow of electrical current with a constant resistance.
• What is the definition of resistance in an electrical component?

  Resistance is the opposition to the movement of electrical charge through it.
• How is resistance measured?

  Resistance is measured in ohms.
• What is a variable resistor?

  A resistor where the value of the resistance can be changed.
• How does a thermistor work?

  Its resistance decreases as temperature increases.
• What is a light-dependent resistor (LDR)?

  A resistor whose resistance depends on light intensity.
• What happens to the resistance of an LDR in bright light?

  The resistance decreases as light intensity increases.
• What is the function of a semiconductor diode?

  It allows current to flow in one direction only.
• What is the difference between alternating current (AC) and direct current (DC)?

  AC regularly changes its direction and size, while DC flows in one direction only.
• What is the role of a diode in an electrical circuit?

  A diode converts alternating current into direct current.
• What are the common components found in electrical circuits?

  • Switch
  • Lamp
  • Fixed resistor
  • Variable resistor
  • Thermistor
  • Light-dependent resistor (LDR)
  • Semiconductor diode
• What are the characteristics of a thermistor and an LDR?

  • Thermistor: Resistance decreases with increasing temperature.
  • LDR: Resistance decreases with increasing light intensity.
• What are the differences between fixed and variable resistors?

  • Fixed resistor: Resistance value is constant.
  • Variable resistor: Resistance value can be changed.
• What is the state of a switch when it is open?

  The circuit is incomplete.
• What is the state of a switch when it is closed?

  The circuit is complete.
• What is the function of a lamp in a circuit?

  To convert electrical energy into light energy.
• What does a voltmeter measure?

  The voltage across two points in a circuit.
• What does an ammeter measure?

  The current flowing through a circuit.
• What is the purpose of a resistor in a circuit?

  To limit the current flowing through the circuit.
• What is an LDR?

  A light-dependent resistor that changes resistance based on light intensity.
• What is a thermistor?

  A temperature-dependent resistor that changes resistance based on temperature.
• What is a variable resistor?

  A resistor whose resistance can be adjusted.
• What is the function of a diode in a circuit?

  To allow current to flow in one direction only.
• What is an LED?

  A light-emitting diode that emits light when current flows through it.
• What is the purpose of a fuse in a circuit?

  To protect the circuit by breaking the connection if the current is too high.
• What is a cell in a circuit?

  A device that converts chemical energy into electrical energy.
• What is a battery in a circuit?

  A combination of two or more cells connected together.
• What is the current behavior in a series circuit?

  The current is the same everywhere
• How is voltage distributed in a series circuit?

  The voltage is shared between components
• What happens to the potential difference in a parallel circuit?

  The potential difference is not shared; each component gets full voltage
• How does the total resistance in a parallel circuit compare to the smallest resistance?

  The total resistance is less than the resistance of the smallest component
• What color is the earth wire in a plug?

  Yellow & green
• What is the color of the neutral wire in a plug?

  Blue
• What color is the live wire in a plug?

  Brown
• What is the function of the live wire?

  It is where the current enters the device
• How does the neutral wire function in a plug?

  It connects the cable in the wall and completes the circuit