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The National MagLab Carlos R. Villa K-12 Education Outreach Coordinator Before we begin… This presentation is available to download at: https://nationalmaglab.org/education/ NHMFL Overview →One of twelve high magnetic field labs in the world → Only one in western hemisphere → Largest and highest powered in the world NHMFL Overview →User laboratory →Over 1350 user visits (2013) →NSF & State of Florida funded →Research free to scientist →Must share research →Research in many fields (Not just magnets!!) →Materials – Energy - Life →Includes Materials Science, Physics, Engineering, Chemistry, Biology, Biomedical, Geochemistry, Microscopy, etc… Center for Integrating Research & Learning → Educational component of NHMFL’s grant → RET programs (more on that later…) → K-12 education outreach → 6,000 students visited this school year → Professional development → Workshops and conferences → CIRL on Facebook Magnet Review → Gauss → Measurement of magnetic field → Named for Carl Friedrich Gauss → Tesla → Measurement of larger magnetic fields → Named for Nikola Tesla → 10,000 Gauss = 1 Tesla Some Magnetic Fields (In Tesla) →Refrigerator magnet: →Earth’s magnetic field: →Person’s magnetic field: →Junkyard magnet: →MRI magnet: .03 T .000045 T 3 x10-13 T 1T 2-3 T Some NHMFL Magnetic Fields → NHMFL ICR magnet: 9.4 T → Ionic Cyclotron Resonance → NHMFL 900 Mhz 21 T → Nuclear Magnetic Resonance → NHMFL resistive magnet → NHMFL split cell → NHMFL hybrid magnet 20-35 T 25 T 45 T → Resistive and superconducting → NHMFL pulse magnet → Not continuous field 100.7 T 1269: Peregrinus 1. Magnetic fields can act at a distance 2. Magnets can only act on other magnetic materials 3. Opposite poles attract and like poles repel 4. When suspended, north poles point North and south poles point South. 1600: Gilbert →Published De Magnete →Earth is a magnet →First critical research on magnets →Used lodestone →Dispelled superstitions and myths 1820: Oersted • An electrical current can create a magnetic field • Oersted set up lecture demonstration – Used battery to supply current – Showed compass needle deflecting near the wire 1820: Ampere • Moving electrical charges produce magnetic fields • Simple experiment – Two straight wires – Current passed through – Wires bowed toward or away • Led to electromagnets 1824: Sturgeon →First Electromagnet →Iron →Copper wire →Electricity 1827: Henry →Improved Electromagnet →Iron →Copper wire →Insulated with silk →Electricity 1831: Faraday →A change in magnetic field produces an electric current →Induction →Magnetic Flux: The change needed to induce current 1835: Lenz’s Law →An induced current in a wire (by flux) will flow to create a field that opposes the flux →Eddy currents created →Used in magnetic braking systems →Rollercoasters →Electric car braking feedback 1900: Free Electron Theory →Electrical conduction in a solid is caused by the bulk motion of electrons →Each metal atom contributes an electron that is free to roam →Voltage briefly accelerates the electrons →Resistance is friction →Each electron is everywhere →Like a wave in a pool 1900: Superconductors Resistance Traditional Metal Superconductor Temperature 1957: BCS Theory → BCS: Bardeen, Cooper, Schreiffer →At low temperatures, some metals lose resistance →Atoms nearly stationary →Superconductivity results from the formation of Cooper pairs →Results in frictionless flow of electrons Resistance →Two electrons partnered →One follows the other Traditional Metal Superconductor Temperature Magnetic Metals → Not all metals are magnetic → 3 are naturally magnetic at room temperature → Iron → Nickel → Cobalt → 2 more are magnetic at lower temperatures → Gadolinium (65 F and below) → Dysprosium (-301 F and below) → Many are magnetic in alloy → Rare-Earth Magnetite & Lodestone → Magnetic mineral → Iron (II, III) Oxide → Fe3O4 → Poor temporary magnet → Largest US deposit in NY (Adirondacks) → Lodestone is magnetized piece of magnetite → Lodestone led to first compass Atomic Theory →Atomos →Indestructible →The atom Proton Neutron Electron Magnetism →Motion of charges particles (electrons) create magnetic fields →In some atoms, spins cancel out →Pauli exclusion →When all electrons spin the same direction: →Magnetic field is produced →Magnetic domains →In magnets: lined up Permanent Magnets → Electrons tend to line up in groups (Domains) → Domains reinforce other domains → Turn material magnetic →Examples: Refrigerator Magnets, Bar Magnets, Magnetite, Horseshoe Magnets, Hematite, etc… → Field can be lost → Curie Point → Electric Current →Degaussing → Bang It Permanent Magnet Activity →Magnet Exploration →Self discovery activity →Group Effort →Communicate your discovery →Share with the class Permanent Magnet Activity → Money is magnetic → Coins are copper-nickel alloy (not magnetic) → Pennies are copper-plated zinc (also not magnetic) → Dollars are printed with iron-rich ink (magnetic!) → Foreign Coins → Canadian, British, Brazilian, Mexican (some)… Permanent Magnet Activity →The Hook: →Blend a $1 →Use a NIB magnet →Pull out the iron Temporary Magnets →Domains temporarily aligned →Will keep magnetic field until tampered →Examples: →Paperclips, scissors, staples, thumb tacks, pins, screwdrivers, refrigerator door, car doors, etc… →Anything that is magnetic, but will not keep its field Temporary Magnet Activities → No rubbing necessary → Magnetism happens almost instantly → They are magnets → North and South → Attract and Repel → Paper Clips remain magnetic → Until something tampers with their field → Field could last years Viewing Field Lines →Field viewers →Iron filings →Use with paper →Clean-up can be a mess →Enclosed viewers →Iron filing case →Mess free! Drawing Field Lines → Seeing fields → Bar magnet → As many compasses as possible Create A Compass → Magnetize an item → Allow it to float → Must turn freely →Needle →Petri dish →Coffee stirrer →Water →Permanent magnet Electricity and Magnetism →The two are so closely related →Where there is electricity, there is a magnetic field →Where there is a magnetic field, electricity can be created Creating Magnetism From Electricity → Electricity is the flow of electrons → In direct current electrons flow in one direction → This alignment of electrons creates a magnetic field around the conductor → Similar to electrons lining up in a permanent magnet → So every wire carrying electricity has a weak magnetic field around it → Coiling the wire concentrates the magnetic field inside the coil Electromagnets → Materials → Copper wire → Iron rod → Battery → Extensions: → 2 batteries →In line? → Aluminum, wooden rod →Will they work? Electromagnets Extensions: → Right hand rule → Direction of field → Poles (Winding direction) → Variables: → Neatness → Number of winds → Wire gauge → Battery strength → Temperature Bitter Plates Bitter Plates Iron In Our Food →Iron in cereal →Total →Baby food →Need a strong magnet →NIB Ferrofluids → A special solution of magnetic particles in a colloidal suspension whose flow can be controlled by magnets or magnetic fields. Cow Magnets Literature Stop Faking It Bill Robertson Driving Force James D. Livingston Literature A Short History of Nearly Everything Bill Bryson The Nature of Science James Trefil Literature The Cold Wars Jean Matricon & Georges Waysand Additional Resources →https://nationalmaglab.org/education →Magnet Academy →https://nationalmaglab.org/education/magnet-academy/ →RET Program →MagLab Educator’s Club Before I Forget →Business cards →Please do not hesitate to contact us with questions, ideas, suggestions, etc… →RET applications: →https://nationalmaglab.org/education/ Research Experience for Teachers 2016 →6 weeks in the summer →$3600 stipend → June 13th – July 22nd → What do you have to do? → Complete online application → Complete program surveys and submit all research data → Send in supporting documents (letter of rec, etc.) Research Experience for Teachers 2016 → What does RET entail? →Research in areas such as Superconductivity, Electricity & Magnetism, Design/Construct Research Instruments, run samples in Electron Paramagnetic Resonance (EPR) or Nuclear Magnetic Resonance (NMR) magnets. RET Logistics and Arrangements → Housing → Stipend → Travel → Program is open to Elementary, Middle, and High School teachers → Pre-service teacher positions available → Focus of the program → Nature of Science → Inquiry → Communicating in science → Experimental Design → Topics for research → Superconductivity → Electron Scanning Microscopy → Condensed Matter FOR MORE INFORMATION Jose Sanchez Assistant in K-12 [email protected] • 850-644-0033 THANK YOU Carlos R. Villa K-12 Education Outreach Coordinator [email protected] • 850-644-7191