The best physics lecturer Walter Lewin makes another wonderful physics demonstration on making a battery out of cans and water.
Walter H. G. Lewin is currently a professor of Physics at the Massachusetts Institute of Technology. He earned his Ph.D. in Nuclear Physics in 1965 at the Delft University of Technology in the Netherlands.Walter Lewin came to MIT in January 1966 with the intent of spending one year in a post-doctoral position, but he never left. He joined an x-ray astronomy group at MIT and conducted all-sky balloon surveys with George W. Clark. Through the late seventies, there were about twenty successful balloon flights. These balloon surveys led to the discovery of five new x-ray sources, which doubled the number known at the time. Furthermore, some of these x-ray sources were found to be varying, and some were x-ray flares. The rockets used by other researchers could not have discovered that the x-ray sources varied because they were only in the air for a few minutes, whereas the balloons could be in the air for many hours. The surveys also resulted in the discovery of GX 1+4, which was the first slowly rotating X-ray pulsar found.Walter Lewin received the "2003 Everett Moore Baker Memorial Award for Excellence in Undergraduate Teaching" award. Some of his lectures are available online in video format.Lewin usually wears a button-down shirt to class, with a pin from his eclectic collection (such as an egg, banana, or smiley face).Many of the Walter Lewin Lectures on Physics at MIT have been shown for over six years on UWTV in Seattle, reaching an audience of about four million people. Lewin personally responded to hundreds of e-mail requests that he received per year from UWTV viewers. For fifteen years he was on MIT Cable TV, with programs aired 24 hours per day helping freshmen with their weekly homework assignments. Lewin also teaches video courses on Newtonian Mechanics, Electricity and Magnetism, and Vibrations and Waves, which can be viewed from the MIT OpenCourseWare web site. His MIT lectures for science teachers and for middle school students can be viewed on MIT World.