Author's Note: How Digital Scales Work
One of the joys of writing for HowStuffWorks.com springs from encountering the surprising delicacy, beauty and complexity to be found in everyday objects. The deft engineering and intricately milled parts that go into these items are, alone, enough to inspire any technophile. Look beyond the appurtenances and appliances to the heart of any device -- particularly one used for measurement -- and you find something even more wondrous: a physical law, ingeniously harnessed to an array of specific and useful tools.
Nowhere is this truer than in scales. In this article alone, I encountered Hooke's law for springs; Pascal's law for fluid pressure; Boyle's law, Charles' law and Gay-Lussac's law describing the behavior of gases; and Ohm's law for electrical resistance -- and that's to say nothing of the various unnamed laws governing stress and strain.
So the next time you encounter some politician who wants to cut science education in the name of balancing the budget, it might be worth reflecting that our most enduring fiscal facilitators, scales, are made possible by a centuries-old march of scientific discovery.
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