Memory Anchor:

• Super Challenge:

  Stretch:

  Challenge:

Key Questions:

1. What are the two equations used to calculate power?
   • The two equations used to calculate power are: P = V I power = potential difference x current P = I2R power = current squared x resistance where: power, P, in watts, W potential difference, V, in volts, V current, I, in amperes, A (amp is acceptable for ampere) resistance, R, in ohms,
2. What is the purpose of everyday electrical appliances?
   • The purpose of everyday electrical appliances are to bring about useful Energy transfers.
3. What does the amount of energy an appliance transfers depend upon?
   • The amount of Energy an appliance transfers depends on how long the appliance is switched on for and the power of the appliance.
4. How do domestic appliances transfer energy from batteries or mains to the kinetic energy of electric motors or heating devices.
   • domestic apliances such as a washing machine will transfer electrical Energy from the mains to kinetic Energy, thermal Energy and sound Energy of the motor inside to turn the drum.
5. How is the power of a circuit device related to the potential difference across it and the current through it?
   • P = IV so Power is the sum of the current mulitplied by the potential difference ( potential Energy x rate of flow)