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Relativity Powers Your Car Battery Feature Summary

Physics in Your World
Relativity Powers Your Car Battery
If you own a car with a lead-acid battery, you might be interested to know that 80% of the voltage comes from Einstein's theory of special relativity. Lead works so well in storage batteries because its atom has a large nucleus, and the innermost electrons rotate at a significant fraction of the speed of light, bringing relativity into play. To learn more, visit this American Physical Society site.

(This feature was updated on March 3, 2014.)
image credit: Shaddack, Wikimedia Commons;  <a href="" target="_blank">image source</a>; <a href="" target="_blank">larger image</a>
image credit: Shaddack, Wikimedia Commons; image source; larger image
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November 1, 2011 - November 15, 2011