Whether they are weighing train cars, big rigs or vegetables in your local grocery, scales are the engines that drive global commerce. Without them, there could be no trade, and laboratories and pharmaceutical companies would have to dream up other ways to assay, mete and dose. Yet most of us are oblivious to the physical laws and clever engineering that go into these pivotal devices. It’s time to weigh in on…
One of the unwritten rules of physics says you can’t get something for nothing; at best, you can swing a fair exchange rate between energy in and energy out. The problem is heat: Like an energy embezzler, it skims off the top of chemical reactions, physical systems and electrical circuits (which is why we can’t have perpetual motion machines).
Superconductors don’t break the laws of thermodynamics, but they do manage to find some fairly large loopholes. Send current through a superconducting wire, and it loses no energy to resistance. Bend the wire into a loop, and it will hold charge indefinitely. Levitate it above a magnet, and the sun will devour the Earth before it will fall.
Plus, it can levitate a frog.