BACKGROUND: Brian Jones, a physics professor at Colorado State University (CSU), runs The Little Shop of Physics, an interactive, touring show of hands-on physics demonstrations that travels all over the United States. Each year, it visits approximately 40 different schools, presenting programs to about 15,000 students from kindergarten to the 12th grade. It also organized teacher workshops, and produces a local cable TV show.
HANDS-ON SCIENCE: The Little Shop of Physics doesnıt show students science, it helps them to do the science themselves: observing, experimenting and questioning. The students learn that science is both fun, and something they can actually do. Since its first year of existence, the show has grown to a rotating collection of more than 75 hands-on science experiments, designed by undergraduate physics students at CSU. Each experiment uses common everyday objects, from old black-and-white television sets, to ketchup packets from McDonalds, common digital clocks, cans of root beer, childrenıs toys, and even the family cat. For instance, connecting a camera flash to a fluorescent light bulb means it can be triggered from a distance by a static charge. The students can set up the experiment to see for themselves, then discuss why this happens.
TRY IT AT HOME! Hereıs an easy and fun experiment to try at home: the Root Beer Float. Youıll need one can of regular root beer, one can of diet root beer, and a large container of water. (A deep sink or a bathtub works well.) Take one can in each hand. They probably feel about the same in size and weight. But when you set both the cans into the large container of water, one of them sinks while the other floats.
WHY THIS HAPPENS: The reason is that different materials have different densities. Things float if an objectıs density is less than that of water, while an object will sink if its density if more than the water. The reason the can of regular root beer sinks while the diet root beer floats, is that sugar has a higher density than the sugar substitute used in diet soft drinks.
The American Association of Physics Teachers contributed to the information contained in the TV portion of this report.