Thermal Conduction (Cambridge O Level Physics)

• Conduction is the main method of thermal energy transfer in solids
• Conduction occurs when:

Two solids of different temperatures come in contact with one another, thermal energy is transferred from the hotter object to the cooler object

• Metals are the best thermal conductors
  • This is because they have a high number of free electrons

Thermal Conduction in a Metal

Conduction: the atoms in a solid vibrate and bump into each other

• Conduction can occur through two mechanisms:
  • Atomic vibrations
  • Free electron collisions

• When a substance is heated, the atoms, or ions, start to move around (vibrate) more
  • The atoms at the hotter end of the solid will vibrate more than the atoms at the cooler end
  • As they do so they bump into each other, transferring energy from atom to atom
  • These collisions transfer internal energy until thermal equilibrium is achieved throughout the substance
  • This occurs in all solids, metals and non-metals alike