Reducing energy loss

• Which type of heat loss do foam seals around windows and doors help to minimise?

  Convection - reduce air flow
• Features of a house which help reduce heat loss by conduction?

  Double glazed windows

  Walls made of material with low thermal conductivity

  Cavity walls
• What is the purpose of putting insulating foam in cavity walls?

  To minimise air convection currents.
• Single glazed windows only have 1 pane of glass.

  Reduce heat loss by convection.
• Double glazed windows have 2 panes of glass, which reduces heat loss by convection.

  Small air gap between 2 panes, minimises conduction.
• Friction


  The resistance that an object encounters when moving across a solid or a liquid.
• Reduces friction between two surfaces?

  Lubricant
• Fast moving vehicles eg cars have a

  streamlined shape to reduce friction from air resistance. This allows them to use less fuel.
• Why does cavity wall insulation contain pockets of trapped air?

  Air is a good insulator.