Reducing energy lost

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

  Reducing unwanted energy transfers
• What is the purpose of thermal insulation and lubrication?

  To reduce energy loss
• How can you suggest reducing energy loss in an exam question?

  By understanding the principles discussed
• What do most people prefer for their homes?

  A warm environment
• Why do we need to reduce heat energy loss in homes?

  To keep the home warm in cold weather
• What is convection?

  Heat transfer through liquids and gases
• How do foam seals help in homes?

  They prevent air from escaping
• What is conduction?

  Heat loss through solids
• How do thick walls help in reducing heat loss?

  They are made from low thermal conductivity materials
• What are cavity walls?

  Two layers of bricks with an air gap
• Why is air a poor conductor?

  It does not transfer heat well
• What is the problem with air gaps in walls?

  They allow convection to occur
• How does insulating foam work?

  It has isolated air bubbles to reduce heat loss
• How does double glazing reduce heat loss?

  It has an air gap that reduces conduction
• What is friction?

  Resistance when moving over a solid or fluid
• Why is friction a problem in energy transfer?

  It reduces efficiency and causes heating
• What is the difference between single and double glazing?

  Single has one pane, double has two
• How can oil help in reducing friction?

  By acting as a lubricant
• How does streamlining affect cars and planes?

  It reduces air resistance and fuel use
• What is the main benefit of reducing friction in vehicles?

  Improved energy efficiency
• What are the methods to reduce unwanted energy transfers in homes?

  • Use thermal insulation
  • Apply lubrication
  • Seal gaps to prevent convection
  • Use thick walls with low thermal conductivity
  • Implement cavity walls with insulating foam
  • Utilize double glazing for windows
• What are the effects of friction on energy transfer?

  • Reduces efficiency of energy transfer
  • Causes heating of objects
  • Makes movement harder (e.g., cycling)
• How do insulation and lubrication contribute to energy efficiency?

  • Insulation prevents heat loss
  • Lubrication reduces friction
  • Both enhance overall energy efficiency