Heat Transfer

• There are two different types of energy explored in previous videos: sound energy and light energy, which also exist in the form of waves.
• In this video, we will explore heat energy and how heat transfer can occur.
• When the woman fills the mug with boiling coffee, the mug and the metal spoon will feel hotter.
• The mug and metal spoon feel hotter


  Because of heat transfer
• Thermal energy


  The energy possessed by an object or system due to the movement of particles within the object or the system
• Heat


  The energy that is transferred from a body with a higher temperature to a body with a lower temperature
• Temperature


  The relative hotness or coldness of an object, measured by a thermometer
• The three common temperature scales are Celsius, Fahrenheit, and Kelvin.
• The SI unit for heat is Joules.
• The natural flow of heat is always from a hotter substance to a colder substance or from a substance with a higher temperature to a substance with a lower temperature.
• Heat transfer


  • It is the process where thermal energy is exchanged between two objects due to their temperature differences.
• The three methods of heat transfer


  • Conduction
  • Convection
  • Radiation
• Conduction


  Heat transfer between objects that are in contact with each other, where heat energy is directly transferred through a material.
• Good conductors of heat


  • Silver
  • Copper
  • Steel
  • Aluminum
• Insulators


  Materials that transfer heat poorly
• Convection


  Heat transfer through the circulation of liquid and gas, where heat energy is transferred by the rising or sinking of matter due to density differences.
• Convection in boiling water


  • The water molecules at the bottom become less dense and rise, while the cooler and denser molecules from the surface sink, creating convection currents.
• Radiation


  Heat transfer through empty space, such as from the sun to the earth, by means of electromagnetic waves.
• We feel the heat coming from the sun because of radiation.
• Heat


  Flow of thermal energy

  Energy in transit

  The energy that transfers from a body with a higher temperature to a body with a lower temperature

  The transit of energy is due to temperature difference
• Heat


  The total energy of the motion of the molecules of a substance

  SI UNITUNIT: JOULES
• Temperature


  Can be measured using thermometer
• Conduction


  Takes place between objectobjects that are in direct contact with each other

  Most effective in solids
• Conductors


  Material that transfer heat poorly
• Methods of Heat Transfer

  Conduction - like heat to pan to food

  Convection-boiling water, rising and sinking

  Radiation- heat of a sun to the earth