Corona effect, also known as corona discharge, is primarily a high-voltage transmission line phenomenon, but it is also seen surrounding lightning rods. Years ago, I was talking with a dairy farmer in Northern New England. We were inside his barn and had a clear view of the old farmhouse through the open door. It was […]
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Changes coming in electrical grid systems
The technology behind the world’s electrical grids is likely to change dramatically in the future with the spread of renewable energy sources such as wind and solar power. The controls handling grid functions can get to be complicated in such distributed energy environments. But it is easier to understand these trends when one has a […]
Contest winners will get an expenses-paid trip to see Hannover Fair in Germany
A few lucky winners will get a glimpse at the global manufacturing industry’s most exciting innovations at the largest industrial trade show and fair in the world, the Hannover Fair in Germany. If Hannover has been on your bucket list, now’s your chance to come over as the guest of Rittal, the world’s largest enclosure […]
Resistivity, conductivity, and Kirchhoff’s laws
Electrical resistivity (specific electrical resistance) and electrical conductivity (specific electrical conductance) are not at all the same as resistance and conductance. They are intrinsic properties that quantify the degrees to which various materials oppose or permit the flow of electric current. Glass, for example, has high resistivity and low conductivity, but it would be meaningless […]
Differences between satellite radio, TV, and internet
For the many homes and businesses beyond the reach of cable, satellite internet is a viable alternative. Two big players in this arena are HughesNet and WildBlue. The technology resembles satellite TV but there are significant differences. Both make use of geostationary (as opposed to merely geosynchronous) satellites, so the receiving dishes are permanently aimed […]
Gauss and his demagnetization circuit
Carl Friedrich Gauss was a brilliant mathematician whose insights and writings laid the groundwork for much of what is known today concerning number theory, algebra, differential geometry, orbital mechanics, matrix theory and numerous other topics. Electronics students are familiar with the gauss as the cgs unit of magnetic flux density. It is defined as one […]
Calculating pi
Pi (the Greek character is π) is the symbol we use to designate the ratio of a circle’s circumference to its diameter. Ancient people, among whom there were many master builders and surveyors, seemed quite interested, and they expended considerable mental energy in attempting to calculate its value. They endeavored also to “square the circle” […]
Schrödinger’s equation and the half-dead cat
Erwin Schrödinger was born around the time of the Michelson-Morley Experiment, but he was pre-eminently a twentieth-century theoretician. He lived until 1961, witnessing during his life gigantic upheavals in science, culture and world politics. He is well-known today for his quirky yet profoundly provocative Schrödinger’s Cat thought experiment. It depicts the paradox of a cat […]
Basics of lasers
Optical lasers all operate according to the same fundamental principles despite the fact that there is considerable variation in the details, particularly in regard to scaling. Small, hand-held laser pointers may be energized by single AAA dry cells while the largest lasers are huge machines powered by nuclear reactors. All lasers consist of resonant cavities. […]
What does antimatter matter?
There are two types of quantum mechanical particles, fermions and bosons. Bosons comprise what is commonly called energy, and fermions are matter. Einstein theorized, and it was later verified by observation, that matter translates into energy in accordance with the formula E = MC2 where C is a constant equal to the nominal speed of […]