| a) The transfer of energy by conduction, convection, evaporation and condensation involves particles, and how this transfer takes place. |
Candidates should:
- understand in simple terms how the arrangement and movement of particles determine whether a material is a conductor or an insulator.
- understand the role of free electrons in conduction through a metal.
- be able to use the idea of particles moving apart to make a fluid less dense, to explain simple applications of convection. |
See the Heat Transfer summary.
A good understanding of the structure of matter in different states is important.
See the notes on the particle theory and the vid clips that accompany it.
See density notes
See expansion notes |
| b) The factors that affect the rate of evaporation and condensation. |
Candidates should be able to:
- explain evaporation and the cooling effect this causes using the kinetic theory.
- explain the design of devices in terms of energy transfer, for example, cooling fins. |
An understanding of the distribution of energies within a sample of liquid or gas is necessary here. |
c) The rate at which an object transfers energy by heating depends on:
■ surface area and volume
■ the material from which the object is made
■ the nature of the surface with which the object is in contact. |
Candidates should be able to explain animal adaptations in terms of energy transfer, for example, relative ear size of animals in cold and warm climates |
This is dealt with in the U-values page. |
About this site
