Presentation on theme: "Basic Magnetic Properties"— Presentation transcript:
1 Basic Magnetic Properties Magnets are fun to play with.
2 Magnetic materialsCertain materials are “magnetic” or can retain magnetic properties. These include iron, nickel, and cobalt.Magnetic materials were originally found in the ground.Today magnets are “made” by placing materials in a strong magnetic field
3 The Poles Magnets have a North and South pole The Poles exist together in pairs, can’t separate a North from a South
4 Magnetic field lines Field lines leave the North and enter the south A compass (which is a magnet) aligns itself with the North pointing in the direction of the magnetic field lines
5 Making MagnetsMagnets are made by placing magnetic materials in a strong magnetic fieldIn these materials the little magnetic dipoles all line up, creating a North at one end and a South at the other.
6 Why does magnetism exist? Magnetism exists because moving charges create magnetic fields.These moving charges create little baby magnets inside the material. When all these little baby magnets line up, they create one big magnet
7 Break a magnet in half?Breaking a magnet in half just creates two smaller magnets
8 Earth’s magnetic field The earth has a magnetic field.A compass aligns itself with this field, with the North side of the compass point towards the magnetic South.We call the North pole the North pole because the North on the compass points in this direction.The “North Pole” is actually magnetically SouthThere is evidence that every few gazillion years the poles reverse.The magnetic fields are important for our survival as they deflect charged particles flying at us from the sun.