Science in the Library

Monday's hands-on science program, "The Science Behind Recording Music," challenged tweens to come up with several iterations of a gramophone that could play the sound stored on a vinyl record with only their hands to power it. First, tweens learned about the history of sound recording and its great inventors, from Leon Scott to Alexander Graham Bell, to Edison to Berliner. I engaged the kids in some fun questions to test their critical thinking skills, like: "How many grooves are on each side of a record?" and "How many times a second would a record turn if it's turning at 33 1/3 revolutions per minute?" Here are my slides from that presentation: Science of Recorded Music from AnnMarie Ppl And here is the video I created to give them a sample of what they would be doing: Then we started spinning records of our own. We made a gramophone out of a tin can, aluminum foil, and a pin, and lowered the pointy end of the pin onto the...

Today's project was designing a wind-powered water pump! We discussed the history of harnessing the wind to power machines, from Hero of Alexandria's wind-powered pipe organ in the 1st century A.D. to the wind pumps used in Muslim cultures in the Middle East and Central Asia, to the windmills created by the Dutch (which--I didn't know before--could mill grain AND pump water from the ground!). The book I mentioned in our discussion today was called Wind Power , written by Ian Graham and published by Raintree Steck-Vaughn Publishers. We talked about Daniel Halladay, the American inventor of the wind pumps used in farms across America. We talked about the Law of Conservation of Energy, how energy is never created or destroyed, but only changes form--in this case, changing from kinetic energy to mechanical energy, and in wind turbines that power homes, it is also converted to electrical energy. We talked about converting different kinds of motion using a mach...