MAGNETS Magnetic forces – Invisible forces that pull 2 magnets together A magnetic field surrounds all magnets (we call these magnetic field lines)

Magnetic poles (N + and S - ) The area where the magnetic force is greatest Don’t forget…like poles repel each other!!!

Earth’s magnetic poles Magnetic North is off from “geographic” North…why??? Some think it’s due to Earth’s internal heat

What minerals are magnetic? Iron Cobalt Nickel

Magnetic domains Groups of atoms with similar aligned poles Nail (temporary) vs. permanent magnet How can magnetism be reduced? Being dropped or heated Don’t forget…break a magnet, and you now have 2!

Electricity and magnets Moving charges produce a magnetic field (or force) The greater the current, the stronger the field (or force)

Electromagnets A magnetic element wrapped in wire This creates a magnetic field around the wire How do you create a stronger electromagnetic? Increase the loops Increase the amount of iron Increase the current What all uses these things? All electric motors Let’s talk about how a stereo speaker works…