The sun is the first source of heat most people think of.
We feel its heat, specially on a hot day.
This enormous ball of very hot gases produces a tremendous amount of heat (and light).
Long ago, people learnt
to make fire by rubbing
two sticks together.
This rubbing action made glowing wood dust.
If the dust fell onto a pile of dry leaves and tiny bits of wood, a fire could be started.
Science – Unit 4 – Lesson 1 – image – Flint
Later, people discovered that striking a stone called flint against a harder rock containing iron produced sparks.
Try rubbing your hands together slowly.
Then try rubbing your hands together quickly.
What do you notice?
Today, electricity is a common source of energy used to produce heat.
Electricity is used to heat up water in kettles or in hot water systems.
It is used to heat up irons, cook food in ovens and toast bread in toasters.
Many types of heaters work by electricity.
Science – Unit 4 – Lesson 1 – image – kitchen appliances
Put your hand on the back of a fridge, computer or television after it has been turned on for a while.
You will feel heat as some is produced in making the appliance work.
Summary of student page information
Activities for students to complete
An experiment to consolidate learnings