In a Flash

Heat or thermal energy

Thermal energy (also called heat energy) is produced when a rise in temperature causes atoms and molecules to move faster and collide with each other.

The energy that comes from the temperature of the heated substance is called thermal energy.

Burning Questions

What is thermal energy?

Thermal energy is energy that comes from a substance whose molecules and atoms are vibrating faster due to a rise in temperature.

How is thermal energy produced?

The molecules and atoms that make up matter are moving all the time. When a substance heats up, the rise in temperature makes these particles move faster and bump into each other.

Thermal energy is the energy that comes from the heated up substance. The hotter the substance, the more its particles move, and the higher its thermal energy.

What are some examples of thermal energy?

Here are some everyday examples of thermal energy that you'll be familiar with:

The warmth from the sun

A cup of hot chocolate*

Baking in an oven

The heat from a heater

*Let's think about that cup of hot chocolate...

The hot chocolate has thermal energy from its vibrating particles. When you pour some cold milk into your hot chocolate, some of this energy is transferred from the chocolate to the particles in the milk.

So what happens? Your hot chocolate cools down because it lost some of its thermal energy to the milk.
The tea has thermal energy from its vibrating particles. When you pour some cold milk into your hot tea, some of this energy is transferred from the tea to the particles in the milk.

As cold particles heat, they contain more energy and so vibrate and separate.

Some matter changes from solid to liquid to gas as its particles heat, vibrate and separate.

What Do You Mean?

Boiling a kettle is an example of both thermal and kinetic energy.

Thermal energy comes from a substance whose molecules and atoms are vibrating faster due to a rise in temperature.

Heat energy is another name for thermal energy.

Kinetic energy is the energy of a moving object. As thermal energy comes from moving particles, it is a form of kinetic energy.

Cool Facts

Ever burnt your hand from picking up something hot?
That's because the thermal energy has been transferred from the hot object to your skin. Ouch!

Speedy Summary

Boiling water on a stove is an example of thermal energy.

Thermal energy is produced when the atoms and molecules in a substance vibrate faster due to a rise in temperature.

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