Physics: Principles and Problems

Chapter 21: Electric Fields

Problem of the Week

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The Touch of a Finger
Possibly once again in the history of man, the touch of a finger will not be just another trivial event. A simple touch may now involve kilobytes of information being transferred. The age of Personal Area Networks, PANs, is at hand.
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PANs
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The natural salinity of the human body makes it an excellent conductor of electric charge. PAN technology takes advantage of skin conductivity by creating an external electric field that passes an incredibly tiny charge over the skin. As the charge flows, it is able to carry digital information. Over 400,000 bits per second can be transmitted this way. Two PAN users can shake hands and instantaneously exchange business cards. People could carry digital versions of their medical files for immediate access by emergency medical personnel. Calling card numbers could automatically be sent from a wallet to a pay phone with only the quick touch of a finger. There are many potential applications for PAN technology.
<a onClick="window.open('/olcweb/cgi/pluginpop.cgi?it=gif::::/sites/dl/free/0078458137/193800/POWproblem1.gif','popWin', 'width=NaN,height=NaN,resizable,scrollbars');" href="#"><img valign="absmiddle" height="16" width="16" border="0" src="/olcweb/styles/shared/linkicons/image.gif"> (0.0K)</a> Brainstorm and then write about other possible applications of PANs. How might PANs be useful in your own life?
 
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