Welcome 21 st Century Scholars June 11, 2009 Presentation by John Swez Emeritus Professor of Physics Department of Chemistry and Physics Indiana State University What is the definition of Physics Websters 9 th new Collegiate Dictionary gives: physics [physica, pl, natural science, fr. Gk, of physikos of nature ] 1. a science that deals with matter and energy and their interactions in the fields of mechanics, acoustic, optics, heat, electricity, magnetism, radiation, atomic structure, and nuclear phenomena The Game of Physics Physics is much like playing a game. The game is to find the rules of nature. We cannot always understand why the rules are what they are, but we can still play the game and test the rules as we play. We test the rules with experiments. Mathematics is used a lot in physics because it communicates the rules of the game in a precise and concise way. As with any other language knowing what certain words and symbols mean is important. For example c is used frequently for the speed of light (3 x 10 8 m/s). Is Physics Magic? There is a scientific explanation for all unusual phenomena that we observe Scientists are not superstitious Scientists apply the Scientific Method The James Randi Educational Foundation can be found atThe $1,000,000 Challenge (see next slide) The $1,000,000 Challenge The Foundation is committed to providing reliable information about paranormal claims. It both supports and conducts original research into such claims. At JREF, we offer a one-million-dollar prize to anyone who can show, under proper observing conditions, evidence of any paranormal, supernatural, or occult power or event. The JREF does not involve itself in the testing procedure, other than helping to design the protocol and approving the conditions under which a test will take place. All tests are designed with the participation and approval of the applicant. In most cases, the applicant will be asked to perform a relatively simple preliminary test of the claim, which if successful, will be followed by the formal test. Preliminary tests are usually conducted by associates of the JREF at the site where the applicant lives. Upon success in the preliminary testing process, the "applicant" becomes a "claimant." To date, no one has passed the preliminary tests. Eddy Currents a rule of nature When a magnet is dropped down a metallic tube, the changing magnetic field created by the falling magnet pushes electrons in the metal tube around in circular, eddy-like currents. These eddy currents have their own magnetic field that opposes the fall of the magnet. The magnet falls dramatically slower than it does in ordinary free fall in a nonmetallic tube. Liquid Nitrogen Demonstration At atmospheric pressure, liquid nitrogen boils at 77 K (196 C; 321 F) and is a cryogenic fluidatmospheric pressurecryogenic We will present some experiments with liquid nitrogen When handling liquid nitrogen safety rules always must be employed which can cause rapid freezing on contact with living tissue, which may lead to frostbitefreezingfrostbite Safety Glasses should always be worn Todays demonstration will show: Measuring the temperature of liquid nitrogen The shrinking balloon and behavior of a tennis ball Ping Pong Ball Spinner Reaction of a bi-metallic strip in liquid N 2 Contraction of metal at low temperatures The water egg Liquid nitrogen ice cream The Meisner Effect The Meisner Effect Just in case I dont have time to show it What you should remember about Physics Fiziks is Phun! Some Important Web Hits[physics 2005.org ]http://www.physics2005.org/[newton.indstate.edu/swez] {my website}http://newton.indstate.edu/swezastr.gsu.edu/hbase/hframe.html {a superb site}http://hyperphysics.phy- astr.gsu.edu/hbase/hframe.html [ ] indicate shortcuts {} comments