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Please come to the front of the lecture hall to see the demonstrations. Please be Seated from Lecture-Demonstration Now on a two-DVD set: The classic four-hour video collection: Demonstrations in Acoustics for only $20. $10 discount for direct cash sales. Inquire in front after program. Dr. Richard E. Berg, demonstrating over 70 experiments, in 29 titled segments, covering vibrations, waves and sound. Physics is Phun e-mail list Go to the Physics is Phun web site and click on “mailing list” link near top of page Link to: SUMMER AND OTHER PROGRAMS FPR PRE-COLLEGE STUDENTS http://www.physics.umd.edu/lecdem/outreach/summerprogs.htm Electricity and Magnetism Physics is Phun January 2009 Topics: Electrostatics Magnetostatics Laws of Electromagnetism Electrostatics Pity the poor neutron; he thought he was a proton but he wasn’t positive. Siphon “Triboelectricity” Quantum mechanical tunneling Charging by Induction Polarization in the Atom Electric forces on polar molecule Polar and Non-Polar Liquids (a) and (b) Electrostatic Force – Moving Lumber Van de Graaff electrostatic generator: simulates lightning from cloud to ground Lightning (1) Lightning (2) Lightning (3) Lightning (4) Lightning (5) Lightning (6) Lightning Video compliments of Tom A. Warner, ztresearch.com 640x480 pixels 7,200 images per second 0.15 seconds recording time Visual aspects: -stepped leaders -dart leaders -return strokes -continuing current Lightning Rod Simulator Lightning striking the Empire State Building Magnetostatics Lodestone Magnet and Magnetic Field Broken Magnet Relations between electricity and magnetism Ampere’s Law: Electric currents create magnetic fields. Lorentz Force: Charges moving in a magnetic field experience an electromagnetic force. Faraday’s Law of Induction: A changing magnetic field creates an electric field. Lenz’s Law: Induced electric currents act so as to oppose the motion that caused them. Magnets dropped through tube Magnetic Levitation Train Levitation Yamanashi test line Maglev site in Japan Magnetic Levitation Trains Photographs compliments of: High Speed Rail (HSR), by Oliver Keating http://www.o-keating.com/hsr/ Maglev Train “Tracks” Train moving on Guideway at 500 mph The Yamanashi Guideway for the MLX01 Electromagnetic Can Crusher Video showing explanation a. current from capacitor creates magnetic field b. increasing magnetic field induces electric field c. electric field moves electrons around can d. electrons feel inward and separation forces e. can cut in two and pushed apart Slow motion of can crusher at Weslyan University Compliments of Vacek Miglus Cyclotron Dee discharge Cyclotron ion source The End See you in March! We are on the web at http://www.physics.umd.edu/lecdem/ Animated Gifs compliments of bellsnwhistles.com