Insulation

• What is the main focus of today's video?

  Reducing unwanted energy transfers
• What are two methods mentioned to reduce energy loss?

  Thermal insulation and lubrication
• Why do people want their homes to be warm?

  To stay comfortable in cold weather
• What is convection in the context of heat loss?

  Heat transfer through liquids and gases
• What is used to seal doors and windows?

  Foam seals
• What are cavity walls?

  Two layers of bricks with an air gap
• How do thick walls help in reducing heat loss?

  They have low thermal conductivity
• Why is air considered a poor conductor of heat?

  Because it does not transfer heat well
• What is the purpose of insulating foam in cavity walls?

  To reduce convection and conduction
• What is the difference between single and double glazing?

  Single has one pane, double has two
• How does double glazing reduce heat loss?

  By having an air gap between glass layers
• What is friction in the context of energy transfer?

  Resistance when moving over a solid or fluid
• How does friction affect energy transfer efficiency?

  It reduces the efficiency of energy transfer
• How does lubrication help in reducing friction?

  By adding oil to moving parts
• What is the effect of streamlining on vehicles?

  It reduces air resistance and fuel use
• What is an example of a lubricant mentioned?

  Oil
• What are the main strategies to reduce energy loss in buildings?

  • Sealing air leaks
  • Using thick walls with low thermal conductivity
  • Installing cavity walls with insulating foam
  • Using double glazing for windows
• What are the consequences of friction in mechanical systems?

  • Reduces efficiency of energy transfer
  • Causes heating of moving parts
  • Makes tasks harder (e.g., pedaling a bicycle)