Heat transfer

• Energy


  The ability to make things move or change
• Matter


  • Anything with mass that takes up space
  • Made up of tiny particles that are always moving
• Thermal energy


  The energy of the moving particles, felt as heat
• Thermal energy


  Heat
• Heat


  • Always moves from a warmer object to a cooler one
  • As heat moves into an object, it becomes warmer
  • As heat moves out of an object, it becomes cooler

  
• Heat transfer


  1. Conduction

  2. Radiation

  3. Convection

  
• Conduction


  Transfer of heat between things that are touching
• Conduction


  • Hands are warmed when holding a hot mug of cocoa
  • A hot stove burner warms a pot sitting on it
• Conductors


  • Objects that allow heat to move through them easily
  • Metals are good conductors
• Conductors


  • Iron
  • Silver
  • Copper
  • Aluminum
  • Stainless steel
• Convection


  • Transfer of thermal energy through liquids or gases
  • Warmer air and water rises and cooler air and water sinks, creating a convection current
• Radiation


  Transfer of energy through electromagnetic waves
• Radiation


  • Radiation from the sun heats objects on Earth
  • Heat travels from fire to objects through radiation
• If 150 J of energy is added to a system when no external work was done, the thermal energy of the system will be raised by 150 J