Presentation on theme: "Magnetism is an invisible force. It pulls metal objects which are magnetic towards a magnet. There are lots of different types of magnets. These include….."— Presentation transcript:
Magnetism is an invisible force. It pulls metal objects which are magnetic towards a magnet. There are lots of different types of magnets. These include….. horseshoe magnets, bar magnets and… circular magnets.
All magnets have two poles – a South pole and a North pole. You can see them marked on these pictures. North pole South pole North pole South pole North pole South pole
Poles that are different attract each other. This means the invisible magnetic force will pull the poles together like this.
Poles that are the same do not attract each other. These will repel. This means they will push each other apart and will not touch or attract each other at all. Attract and repel are opposites.
Some metals are magnetic. Objects made of these metals are attracted to a magnet. Just because an object is made from metal does not make it magnetic. This can is made from aluminium. Will it be attracted to the magnet if we put it underneath? The aluminium can is not attracted to the magnet. Aluminium is a metal but it is not magnetic. This nail is made from iron. Will this be attracted to the magnet if we put it underneath? The nail is attracted to the magnet because iron is a magnetic metal.
Let’s look at some other objects. Can you guess which ones will be magnetic? A paper clip Yes! It’s magnetic A knife This knife is made of steel, which is magnetic. A pencil The pencil is not made from a magnetic material. A ball This ball is made of rubber and is not magnetic. A screw The screw is made from iron, just like the nail. Now, let’s see what you can remember about magnetism.
Are all magnets the same shape? No. There are lots of different types. Here are some of them. horseshoe magnets, bar magnets and… circular magnets.
What do all magnets have? All magnets have a North pole and a South pole. South pole North pole
What do different poles do ? Different poles attract.
What do poles that are the same do ? Poles that are the same repel.
Are all metals magnetic ? No. Only some metals are magnetic Aluminium is not magnetic. Iron is magnetic.