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Predict and test which objects are made of magnetic materials and which are made of non-magnetic materials. Head to ngscence.com for a range of related resources for use in the classroom or at home.

Non-contact Forces – Magnetic Force
Place an iron nail on a table. Slowly move a magnet towards the nail. What do you notice?

A magnet is an object with magnetic force. Magnetic force occurs in an object due to the motion of electrically-charged particles. As you observed when you moved the magnet near the iron nail, magnetic force can act at a distance. It is a non-contact force. It can act through solids, liquids and gases.

Magnetic force can attract objects made of certain metals such as iron and nickel. Magnetic force cannot attract objects made of plastic, wood, rubber or glass.

A magnet has two poles – a North pole and a South pole. It is at each pole that the magnetic force is the strongest.

When the like poles of two magnets are brought together, they push or repel each other. When unlike poles are brought together, they pull or attract each other.

Many objects make use of magnetic force. Some doors use magnets to keep them closed. Magnets are used to stick notes and photographs to refrigerators. They are used in electric motors, loudspeakers and can also be used for medical imaging and storing data on computer disks.

When a magnet is hanging freely, it will come to rest with the South pole pointing in the direction of north and the North pole pointing in the direction of south. A compass is a device that uses this property to find the direction of north.

A maglev (magnetic levitation) train has magnets that repel it from the track. This reduces friction and allows the train to travel at fast speeds.

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