Conductors and insulators of electricity

Different materials have different resistances:

You can easily find out which materials are conductors and which are insulators using a simple circuit. You set up a series circuit with a cell, lamp and wires. Leave a gap in the circuit between two of the wires. Then connect the two wires using pieces of each material and see if the lamp lights up:

  • it will light up if the material is a conductor
  • it will not light up if the material is an insulator

The table lists some examples of conductors and insulators:

ConductorsInsulators
Metal elementsMost non-metal elements, e.g. sulfur, oxygen
Graphite (a form of carbon, a non-metal element)Diamond (a form of carbon, a non-metal element)
Mixtures of metals, e.g. brass, solderPlastic
Salt solutionWood
Liquid calcium chlorideRock
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