Magnetic Fields
The area around a magnetic object which exerts a magnetic force
They are created by moving electric charges (inside the atoms of magnetic objects or within wires)
Law of Magnetic Poles
Unlike poles attract
Like poles repel
Earth’s Magnetic Field
- Generated in our planet’s interior and extends out into space
- Earth has two sets of poles - geographic poles and magnetic poles
- The magnetic poles are relatively close (about 500 km away) from the geographic poles.
The Compass
A magnetized needle is placed on a pivot so that it may rotate freely. Earth’s magnetic field exerts a force on the compass needle, causing it to rotate until it come stop rest in the same direction as the magnetic field (North).