Lesson 7 of 9

Heating and temperature

Goal: Describe how energy moves from hot objects to cold ones.

Puzzles for this lesson

Temperature tells you how hot something is. Thermal energy is the total energy in its thermal store.

The tea is hotter. But the bath holds far more water, so it stores far more thermal energy.

Temperature is measured in degrees Celsius (°C). Thermal energy is measured in joules. It depends on the temperature of an object, its mass and what it is made of.
Energy is transferred from hotter to colder. A hot drink cools as its energy spreads out into the room. This spreading out is called dissipation.
The overall transfer stops when both are at the same temperature. This is called thermal equilibrium.

Your turn

This lesson’s activity starts here in a moment.

I can tell temperature from thermal energy.I can say when the transfer stops.

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Joule The unit of energy

Thermal store Filled when an object is warmed up

Temperature How hot something is, in degrees Celsius

Thermal equilibrium When two objects are at the same temperature

For teachers: AQA 3.3.4 · Cambridge 9Pf.02, 9Pf.04