Power and the National Grid

• Describe the energy transfers that occur for a battery-powered fan

  Chemical —> Kinetic + Heat —> Sound

  (Electrically)
• What is the power rating of an appliance?

  The power rating of an appliance is the amount of electrical power it consumes, typically measured in watts (W).
• What is the National Grid?

  A network of power lines and substations that deliver electricity to homes and businesses.
• Explain why electricity is transferred by the National Grid at a high potential difference but low current:

  As high currents waste more energy than low currents
• What are the function of step-up and step down transformers?

  Step-up transformers increase the voltage of the supply, step-down transformers decrease the voltage of the supply