>-----Original Message----- >From: Joe P Martin [mailto:[email protected]] >Sent: Wednesday, September 11, 2002 3:58 PM >To: [email protected] >Subject: Water + Electricity > > > >Greetings, > >A friend of mine is teaching elementary school students on the >dangers of >mixing water with electricity. However, he also wants to show >examples of >situations where water and electricity mix, yet does not cause >a problem. >Does anyone have any examples? > >Also, does anyone have a great elementary school explanation as to what >elements or conditions are needed to be present before water and >electricity become dangerous? > >All responses are appreciated. > >Joe Martin >Applied Biosystems >[email protected] >
To address your question directly, electroplating, etching and chemical machining come to mind. And certainly, complex life forms have an intricate balance of electric charges and water. However, addressing the question at a more fundamental level, I have a nagging feeling that equating water and electricity with danger is a simplistic view of reality and a disservice to rational education. I would hope that the presenter could try to sneak Ohm's Law into the demo, and maybe focus on how water can be a conductor. But maybe engineers have a problem connecting with average kids. One rainy afternoon, as I pulled into my driveway, I noticed one of my neighbor's kids climbing to the very top of a tree. The tree branches actually reached beyond the level of the utility 220 VAC powerlines, and the kid was only about 6 feet below the lines. I called out to him that those wires were dangerous, and that he shouldn't even be climbing in that wet tree. He replied that he knew what he was doing. Although I'm usually a great believer in learning through experimentation, I tried to rationalize the danger and present it to him at a level he could comprehend. I told him that the wires were electrically hot, that the tree was grounded, and since he was wet and standing in a wet tree, that he was grounded too. He replied that only his father could tell him he was grounded. Maybe you might want to introduce the kids to the classical 120 VAC hot-dog cooker too. Ed Ed Price [email protected] Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA USA 858-505-2780 (Voice) 858-505-1583 (Fax) Military & Avionics EMC Is Our Specialty Shake-Bake-Shock - Metrology - Reliability Analysis ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
