Conductors of Electricity

• Most materials fall into two groups: conductors and insulators.
• A conductor allows electrons to flow through it.
• An insulator is a barrier to electricity.
• An insulator may act as a store of electricity known as static electricity.
• There is a small third group called semi conductors - these are used in electronics.
• The current is carried by ELECTRONS.
• Metals contain a "sea" of free electrons (negatively charged) which flow through the metal.
• This is what allows electric current to flow so well in all metals.
• Electric current will only flow if there are charges which can move freely (electrons).
• There are some things that you need to know for the exam about the difference between CONVENTIONAL and ELECTRICAL current.
• CONVENTIONAL current flows from POSITIVE TO NEGATIVE.
• ELECTRICAL current flows from NEGATIVE TO POSITIVE.
• So electrons flow opposite to the flow of conventional current.