Electromagnetism: Magnetic Fields

Magnetism The phenomenon by which certain materials (magnets) exert forces on each other These forces can be attractive or repulsive The movement of electrons (or current) within certain metals has a magnetic effect All magnets have a north pole and a south pole

Magnetic Field The area around an object in which a magnetic force can be felt Magnetic field lines connect the north and south poles of a magnet They travel from the north pole to the south pole

The Earth's Magnetic Field The Earth has a massive magnetic field around it It acts as if there is a giant bar magnet in its centre This magnetic field is what protects the Earth from solar radiation The location of the north and south magnetic poles are close to, but not in the same place, as the geographic poles

Magnetic Field due to Current When current flows through an object, it creates a magnetic effect To find out the direction of the magnetic force, we use the "Right hand rule" If you curve your right hand around a current-carrying wire, when your thumb is pointing in the direction of the current, your fingers indicate the direction of the magnetic field 

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