Introduction

Magnets and electromagnets have a north-seeking pole and a south-seeking pole. The magnetic fields of these can be shown using diagrams with field lines.

The arrow heads on the field lines go from north to south. Opposite poles of a magnet attract each other.

A wire that carries an electric current in a magnetic field experiences a force and may move. The size of the force can be increased by increasing the size of the current flowing or the strength of the magnetic field.

Magnets attract magnetic materials using a magnetic field

  • The magnetic field surrounds the magnet, and gets weaker as the distance from the magnet increases
  • Magnets should be called permanent magnets > the magnetism is always there
  • Electricity makes a magnet much stronger. This can be turned on and off
  • Magnets can pick up paper clips etc. Electromagnets can pick up cars e.g. scrapyards

This video explains how Metals are made Magnetic

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