Five Perpetual Motion Machines, and Why None of Them Work
To the eccentric inventor, perpetual motion probably seems a low-hanging fruit. Sure, those pesky Laws of Thermodynamics tell us that no machine can do work forever without some sort of energy input, but there's no reason these archaic, esoteric musings can't be overcome. Just a single spark of ingenuity would rattle physics and earn never-ending fame and fortune!
Many have tried, of course, and all have failed.
Let's take a look at a few more notable attempts.
The Overbalanced Wheel. Perhaps the earliest recorded inkling of perpetual motion came courtesy of renowned medieval mathematician Bhaskara in the 12th century. The Indian thinker proposed an "overbalanced" wheel in which weights would swing on one side, applying a greater torque to keep the wheel spinning. A quick glance at the wheel in motion reveals why this idea is doomed to fail. One side of the wheel will always have more weights, thus keeping the torques boringly in balance.
The Self-Filling Flask. Sometime in the 17th century, legendary chemist Robert Boyle proposed a self-filling flask, in which liquid is poured into a cup at one end of the apparatus and flows through a winding tube up and back around into the cap, hypothetically filling forever. The idea was that capillary action, where liquids cling to surfaces via tension and adhesion, will move the liquid up the tube. This process won't fling the water out of the tube, however, as capillary action requires a surface to cling to. Thus, the liquid will never leave the long tube!
The Float Belt. Floating balls attached to a belt enter into a water tank at the bottom through a watertight valve, then float up through the water, spinning the belt in perpetuity. Can you spot the flaw? The same forces that push the balls up through the water push back on the balls trying to enter the water in the first place. The float belt is an innovative solution to perpetual motion, but ultimately inoperable.
Crookes' Radiometer. This strange looking windmill is locked in an airtight chamber at near vacuum conditions, so how the heck is it moving? The answer is light! This isn't a windmill; it's a light-mill! Chemist William Crookes accidentally stumbled upon the effect and created the contraption in 1873. He first surmised that photons were pushing on the dark vanes via radiation pressure, as predicted by Maxwell's theory of electromagnetism, but this was actually incorrect. The correct solution was discovered six years later by Osborne Reynolds. Through a process of "thermal transpiration" light warms gas molecules on the black sides of the vanes, which creep to the edges and flow into the cooler gas molecules on the silver side of the vanes. "The net movement of the vane due to the tangential forces around the edges is away from the warmer gas and towards the cooler gas, with the gas passing around the edge in the opposite direction," UC-Riverside's Phil Gibbs explained.
Newman's Energy Machine. In 1979, American inventor Joseph Newman attempted to patent his new DC motor, claiming it produced more energy than the battery power supplied to it. As he told CNN, his spinning device "utilized energy in a magnetic field consisting of matter in motion," getting pushed just like a water wheel. The Patent Office disagreed and rejected his application. Newman appealed, and his device was subsequently scrutinized by the National Bureau of Standards, which concluded that the contraption's power efficiency never went over 100% (which would support perpetual motion), not even close. The affair received wide media attention in the 1970s and 1980s, but Newman quickly receded from the spotlight when he proved himself to be a complete crank. At one point, he claimed to have married his secretary and her 8 year old daughter, acting on orders from God.