Conduction

Both conduction and convection are methods of energy transfer that require particles. However, in solids, energy is transferred by conduction.

When a substance is heated, its particles vibrate more vigorously and bump into each other. When this happens, energy transfers along the substance via conduction.

A visual representation of "CONDUCTION" showcasing how heat is transferred through direct contact. On the left, a box depicts "HEAT" with red and orange atoms and arrows indicating movement. In the centre, there's a frying pan containing food placed on a burner. Heat from the burner travels through the pan to the food and further to the pot handle, labelled "HEAT TRANSFER". A description reads "Conduction: The Transfer of Heat through a material by Direct Contact".

The diagram below illustrates the arrangement of atoms in a solid, with the colour indicating the temperature of each atom

illustration showing the diffusion of heat through a collection of blue spheres. As heat is introduced, shown by arrows, the spheres transition from blue to red, indicating increasing temperatures. Initially, a singular sphere turns red on the left and right clusters. At the bottom, a central group of spheres depicts varying degrees of heat absorption, with colours ranging from deep red at the source to yellow and then to blue as the heat spreads outward.

  • The more red the atom is, the more heat energy the atom has
  • The more blue the atom is, the less heat energy the atom has

As the atoms start to vibrate more, they collide with neighbouring atoms, transferring heat energy. For example, when a metal spoon is placed into a hot drink, the whole of the spoon ends up becoming hot.

Conductors and insulators

Good conductors are inherently poor insulators, and vice versa. This is because conductors transfer heat easily and insulators do not transfer heat easily.

Good conductors/poor insulators

Metals are examples of good conductors.

When heat moves through a substance, it transfers from one particle to another. Solids are usually the best conductors because their atoms are very close together. This means that when the atoms vibrate, they instantly collide with neighbouring particles.

Good insulators/bad conductors

Some examples of good insulators are:

  • Plastic
  • Air
  • Wood
  • Rubber

Good insulators often act as poor conductors because their particles are spaced further apart. As a result, transferring energy to neighbouring particles is more difficult due to the increased distance between them.