Heat

• Reducing friction with lubrication

  1. Lubricates parts that rub together

  2. Reduces friction
• Thermal conduction


  The process where energy is transferred by vibrating particles in a substance
• Materials with high thermal conductivity

  • Diamond
  • Aluminium
  • Graphite
• Materials with low thermal conductivity


  • Air
  • Steel
  • Bronze
• Insulators


  • Wool
  • Plastic
  • Wood
• Purpose of insulators


  To reduce energy transfers, for example, to keep a house warm or build a soundproof room
• Why fibreglass is a good insulator


  • The air trapped between the fibres makes it a good insulator
  • It has a much lower thermal conductivity than the roof material
• Purpose of cavity wall insulation


  To lower the conduction of heat through the walls from the inside to the outside