Published on March 12th, 2014 | by Roger Chu
Modern Design Tools Measure the Invisible and Make Circuits Safer
Though we see its effects on other things, we cannot see electricity itself. So how can we measure its voltage? Oh, but we can, with modern and even old-fashioned tools. In fact, measuring something is really making a comparison. We take a known (a standard or a reference) quantity and compare it to the unknown quantity.
Mechanical Measurement Of The Visible Over Millennia
Though electricity is invisible, we can see its effects and measure them. Someone without a science background may say, for example, “What about lightning?” We do not see electricity, but we definitely see the super-heated air (plasma) glowing brightly. Also, children often place 9-V batteries on each other’s tongue as a joke. We feel the insult to our nervous system, but we cannot see anything. Doctors can probe the brain with small electrical currents, and the patient’s nervous system might “see” light flashes. In each of these examples, we can measure that invisible voltage if we have the right, highly accurate tool.
Full article by Bill Laumeister, Electronic Design