1. Simple Electric Circuits
D. Crowley, 2008

2. Simple Electric Circuits
To know how to set up simple electric circuits, and represent these using symbols and explain the energy transfers taking place

3. Energy & Money
There are many ways a house can be made more energy efficient, however some of these techniques are more cost-effective than others
Complete the saving energy and money worksheet

4. Energy & Money
Payback time – eventually the money saved per year on reduced heating bills will equal the initial cost of the insulation
Insulation Type
Cost
Saving Made In 1 Year
Payback Time
Double Glazing
£3000
£150
20 Years
Loft Insulation
£400
£200
2 Years
Cavity Wall Insulation
£1000
£100
10 Years
Draught Excluders
£50
£10
5 Years
Hot Water Tank Blankets
£25
2.5 Years

5. Energy There are 10 types of energy: -
Light energy - from the sun; a light bulb etc…
Sound energy - from a loudspeaker; a drum etc…
Kinetic (movement) energy - anything which moves!
Nuclear energy - transferred during a nuclear reaction
Thermal (heat) energy - transferred from hot objects to colder ones
Radiant heat (infra red) energy - transferred as electromagnetic radiation by hot objects
Gravitational potential energy - possessed by anything with the ability to fall
Elastic potential energy - stretched springs; elastic and rubber bands etc…
Chemical energy - possessed by food; fuels; batteries etc
Electrical energy - a current in a circuit etc…

6. Electricity
Energy can never be created or destroyed, it can only ever be converted from one form to another
Energy is only useful when it is converted from one form to another
Electricity is so useful because it can be easily transferred…

7. Electricity
Electricity is the flow of electrical power (charge) in the form of electrons
Electricity is a useful secondary energy source – most energy sources (like coal, oil, nuclear, wind etc…) can be converted into electricity

8. Circuits
A bulb in the circuit is like a radiator – an electrical device uses electrical energy, supplied by the circuit
The wires are like pipes - they carry the flow of electricity (current) around the circuit
The electrical current is pushed by the cell (battery) – this is the voltage
The electrons flow from –ve to +ve
Cell + -
Wires
Lamp

9. Wires forming a complete circuit
Electrical Circuits
An electric current needs two things: -
Something to make the electricity flow (battery or power pack)
A complete circuit
Without these two basic things, an electric current will not flow
Cell + -
Wires forming a complete circuit

10. Component Diagrams
Circuit symbols are used to show the components in an electrical circuit (wires are represented by straight lines)

11. Symbols
Complete the simple electric symbols worksheet

12. Symbols

13. Task – to set up simple circuits
Draw the circuit diagram in your book
Explain what energy transfers are taking place
e.g. bulb energy transfer:
electrical heat & light (if there is a bulb in your circuit))
Cell + -
Wires
Switch
Lamp

14. Quiz