Revise GCSE Physics


Question: What happens to the energy of the object when we heat it, exactly?

When we heat an object, the energy either:

1. Increases the average vibrational energy of all the particles in the object; which means the object's temperature increases.

Or

2. Is used to overcome the intermolecular forces in the object; which means the object changes state.



Very advanced stuff below here - will make your eyes bleed - DO NOT READ if you are doing exam revision!

When we heat an object we increase the amount of one of the two forms of energy, Kinetic Energy OR Potential Energy, always one at a time - Never both at once!

The amount of heat energy transferred into the object equals the increase in total energy and equals the increase in either Potential or Kinetic, whichever is changing.

When we are dealing with heating the Kinetic Energy of the particles is usually called the Thermal Energy and the Potential Energy is usually called the Latent Energy. 'Thermal' means 'to do with temperature' and 'latent' means 'hidden'.

Potential energy and Kinetic Energy are often abbreviated to PE and KE respectively.

We said above that when we heat an object, either its temperature rises or it changes state.This is directly related to the fact that the object contains two types of energy and the fact that only one changes at a time.

When an object's Thermal Energy changes, it's Temperature changes.

When an object's Potential Energy changes, it's State Changes.

Angry face