WELCOME BACK MINIONS Warm Up Is On The Board

WARM UP QUESTIONS How can an atom behave like a magnet? How are Magnetic Domains arranged in a magnetic material? How can magnets be changed?

ATOMIC FLASHBACK An atom contains neutrons and positively charged protons in its nucleus. Negatively charged electrons move randomly throughout an atom.

ELECTRON SPIN Electron Spin A spinning electron produces a magnetic field that makes the electron behave like a tiny magnet in an atom. In an atom, most electrons tend to form pairs where each spin in opposite directions of each other, cancelling out the magnetic charge. BUT!!! Some atoms contain electrons that are not paired. These atoms tend to have strong magnetic properties!

MAGNETIC DOMAINS Most material have their magnetic fields point in random directions. This cancel each other out entirely.

MAGNETIC DOMAINS In a magnetized material, all or most of the magnet domains are arranged in the same direction.

MAGNETIC DOMAINS Modern magnets come in a variety of shapes and are made from many different materials.

MAGNETIC MATERIALS Ferromagnetic Material A material that shows strong magnetic properties. Tend to be made of alloys. Example: Alnico (Aluminum, Nickel, Iron, Cobalt) Most magnets made from Ferrite Mixture of substances that contain ferromagnetic elements. Stronger & less expensive that metal magnets.

WORLD’S STRONGEST MAGNET National High Magnetic Field Laboratory Florida State University 500,000 times stronger than Earth’s Magnetic Field Custom built split magnet

MAKING A MAGNET The easier it is to make an object magnetized, the quicker the object loses its magnetism. Temporary Magnet The harder it is to magnetize an object, the longer the object stays magnetized! Permanent Magnet

MAKE A MAGNET

DESTROY A MAGNET A couple of ways… Strike the magnet. Knocks the domain out of alignment Heating the magnet. Heat = more random movement. Makes it difficult to keep domains aligned!

BREAKING A MAGNET Each piece of a magnet retains its magnetic properties after it is cut in half.

WRAP-UP How can an atom behave like a magnet? How are Magnetic Domains arranged in a magnetic material? How can magnets be changed?

TICKET OUT THE DOOR… 1 st Column What does it take to make a magnet? 2 nd Column What does it take to destroy a magnet? 3 rd Column What happens when you break a magnet?