Prefixes and suffixes

A root word is the simplest form of a word. It can have beginnings and endings added to it. When we combine root words with beginnings or endings, it creates new words. These are called prefixes and suffixes.

Prefixes and suffixes can something have their own meaning

E.g. Re means again
Tri means three
Un means not

We can read and write complex words when we see the links between known words and new and when we use knowledge about word families.

Prefix Suffix text

Friction

Friction

Friction is a force between two surfaces that are sliding, or trying to slide, across each other. For example, when you try to push a book along the floor, friction makes this difficult.

Friction always works in the direction opposite to the direction in which the object is moving, or trying to move. Friction always slows a moving object down.

The amount of friction depends on the materials from which the two surfaces are made. The rougher the surface, the more friction is produced. Friction also produces heat. If you rub your hands together quickly, you will feel them get warmer.

Friction can be a useful force because it prevents our shoes slipping on the pavement when we walk and stops car tyres skidding on the road. When you walk, friction is caused between the tread on shoes and the ground. This friction acts to grip the ground and prevent sliding.

Sometimes we want to reduce friction. For example, we use oil to reduce the friction between the moving parts inside a car engine. The oil holds the surfaces apart and can flow between them. The reduced friction means there is less wear on the car’s moving parts and less heat produced.

Ice causes very little friction, which is why it is easy to slip over on an icy day.

However, this is a good thing for ice skating and sledging.

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