Thermal Insulator

Key Stage 3

A thermal insulator is a material that does not allow thermal energy through easily by conduction.

Non-metals usually make the best thermal insulators.

Metals make poor thermal insulators.

Gases make good thermal insulators.

A thermal insulator is a material with a low thermal conductivity.

Thermal insulators can be used to prevent objects from changing temperature.

Good thermal insulation around a house can help to keep the contents warm in winter and cool in summer.

When two objects close to one another are at different temperatures energy will be transferred from the hotter object to the cooler one until they are both the same temperature. They are said to be in thermal equilibrium.

Thermal insulators can reduce the rate at which energy is transferred between objects of different temperature.

The effectiveness of a thermal insulator is affected by two factors:

Thermal Conductivity - The lower the thermal conductivity the better the material is as an insulator.
Thickness - The thicker the material the better it will be at reducing energy transfer and the more effective the insulation.