Chapter 18.1 – Magnets and Magnetic Fields all magnets have magnetic poles – points at the ends of a magnet that have opposing magnetic qualities all magnets have a north pole and south pole that are magnetically opposite like poles repel and unlike poles attract

Chapter 18.1 – Magnets and Magnetic Fields it is impossible to separate the south pole of a magnet from its north pole if you cut a magnet in two each piece will still have a north and south pole so you will have 2 north poles and 2 south poles permanent magnets – substance that is magnetic all the time

Chapter 18.1 – Magnets and Magnetic Fields magnetic materials are magnetically hard or soft hard magnetic materials are difficult to magnetize and do not lose their magnetism easily ex. cobalt, nickel soft magnetic materials are easy to magnetize and lose their magnetism easily ex. iron magnets can only lift metals that can be magnetized because they become temporarily magnetic

Chapter 18.1 – Magnets and Magnetic Fields a region where a magnetic force can be detected causes the attraction or repulsion of a magnet moving charges create magnetic fields; i.e.: electrons orbiting an atom groups of atoms align their magnetic fields with each other magnetic domains – groups of atoms with aligned magnetic fields or poles in an unmagnetized object the domains are arranged randomly in a magnetized object the domains are aligned together

Chapter 18.1 – Magnets and Magnetic Fields we can use magnetic field lines to represent magnetic fields magnetic field lines always form closed loops magnetic field lines go out from the north pole and into the south pole the further from the magnet, the weaker the magnetic field

Chapter 18.1 – Magnets and Magnetic Fields magnets try to align themselves with other magnetic fields compass – a magnet on a pivot that can rotate freely the Earth gives off a magnetic field from the motion of the iron core the Earth’s north magnetic pole is in Antarctica this is why the north pole on a compass points north it is aligning with the Earth’s magnetic field and is pointing to the south magnetic pole

Chapter 18.1 – Magnets and Magnetic Fields the Sun also has a magnetic field and so do other planets charged particles entering the atmosphere near the poles cause the Northern and Southern lights many animals use the Earth’s magnetic field to navigate