Lesson Plan: P1.3.03

Hamble Lesson Observation Plan
Learning About
How can we calculate the power of an appliance?
Keywords:
  • Ohms: the SI unit of electrical resistance, transmitting a current of one ampere when subjected to a potential difference of one volt. (1)
  • Current: The ordered directional movement of electrically charged particles. (1)
  • Power: The amount of energy transferred per unit of time. (Expressed in Watts) (1)
  • Charge: The physical property of matter that causes it to experience a force when placed in an electromagnetic field. There are two types of electric charges; positive and negative. (1)
Memory Anchor:
Method Precise Learning Objective Linked Question / Activity
(Designed for maximum working out)		 Stepping Stones Pitstop Check
(Thinking Map)
Students should be able to explain how the power transfer in any circuit device is related to the potential difference across it and the current through it, and to the energy changes over time: power = potential difference ? current P = V I power = current2 ? resistance P = I2 R 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, ? What are the two equations used to calculate power?

Demo the equations for calculating power. Students to apply.
Everyday electrical appliances are designed to bring about energy transfers. What is the purpose of everyday electrical appliances?

Investigate a number of electrical appliances, either around the lab or well-known devices, eg a TV, to look at the energy transfers that occur.
The amount of energy an appliance transfers depends on how long the appliance is switched on for and the power of the appliance. What does the amount of energy an appliance transfers depend upon?
Students should be able to describe how different domestic appliances transfer energy from batteries or ac mains to the kinetic energy of electric motors or the energy of heating devices. How do domestic appliances transfer energy from batteries or mains to the kinetic energy of electric motors or heating devices.
Students should be able to explain how the power of a circuit device is related to the potential difference across it and the current through it How is the power of a circuit device related to the potential difference across it and the current through it?
Links To the Big Ideas
ForcesParticlesEnergyCells