Conduction of Heat (Edexcel GCSE Physics)

Factors Affecting Conduction

• Thermal conduction is the process where energy is transferred by vibrating particles in a substance

• The vibrating particles transfer energy from their kinetic store to the kinetic store of neighbouring particles

• The direction of energy transfer is always from hot to cold

  The higher the thermal conductivity of a material, the higher the rate of energy transfer by conduction across the material

• Materials with high thermal conductivity heat up faster than materials with low thermal conductivity

Materials with high and low thermal conductivity

• Objects will continue to lose heat until they reach thermal equilibrium (equal temperature) with their surroundings

  • For example, a mug of hot coffee will cool down until it reaches room temperature    

• Conduction is the main method of energy transfer by heating in solids

  • Metals are extremely good thermal conductors

• Non-metals are poor thermal conductors whilst liquids and gases are extremely poor

  • Poor conductors are called insulators 

Energy is transferred by heating from the hotter foot to the cooler tiles by conduction

• Factors affecting thermal conduction are:

  • The thickness of the material

  • The thermal conductivity of the material

  • The temperature difference between two areas of the material (for example the internal and external surfaces of a wall)

• The rate of energy transfer is reduced by:

  • Increasing the thickness of the material

  • Decreasing the thermal conductivity of the material

  • Decreasing the temperature difference