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Heating and Cooling

HEAT is a measure of the TOTAL thermal energy in an object.

TEMPERATURE is how much thermal energy each MOLECULE has on average (the individual portion of energy in each molecule).

THERMAL ENERGY is the kinetic energy (movement) of individual particles.

Heat energy can move from one place to another in THREE ways:

CONDUCTION: through direct contact (with solid matter only)

CONVECTION: by making a liquid or gas move

RADIATION: through infrared light

Conduction:

An experiment to show conduction:

- Heat a variety of rods of different metals ( brass, copper, iron, aluminium, lead and zinc) all at the same time.

- Before this though, place a bit of petroleum jelly at the top of each rod

You will find that the vaseline melted and fell at different times. This is because the metals heated up at different rates. The metals all conduct heat: this means the heat went through the metals because the molecules were vibrating more vigorously and taking up more space.

Here are some good CONDUCTORS of heat: Here are some good INSULATORS* of heat:

Aluminium Glass

Brass Plastic

Lead Rubber

Copper Cloth

Tin-Foil Wood * These are good i

Iron Brick

Foam

Air