energy
Tracing Power Lines with the Pylon Appreciation Society
Pylons
Not all the towers along a transmission line are identical. Look closely at a tower where the line makes a sharp turn and you will likely find it is wider and beefier than other towers along the route. The added strength and weight are needed to resist the unbalanced pull of the conductors, which might overturn an ordinary tower. These special towers are called deviation or angle towers.
The transmission-line tower everybody knows is an Erector Set latticework of steel girders and diagonal braces. The techniques for designing and building these towers are the same ones used in constructing steel bridge trusses or crane booms. The individual pieces can be made cheaply from rolled steel and then bolted together on the site. This last point is more important than it might seem: transporting a fully assembled tower 100 feet tall is an awkward and expensive business.
A haunting, syncopated music
"Rappers" on the roof of the electrostatic precipitator knock the accumulated dust free, letting it fall into the storage hopper. Each rapper is the size and shape of a baseball bat. Inside is an electromagnet that pulls a steel plunger upward, then allows it to fall again, producing a sharp knock. The rappers are energized at seemingly random intervals, producing a haunting, syncopated music. (The rhythm seemed more modern jazz than rap.)
Safety cut rope axe man
In the first nuclear reactor, constructed by Enrico Fermi in 1942 under the bleachers of the University of Chicago football stadium, the control rods were held up by a manila rope. A man with an axe was told to cut the rope if the reactor got out of hand. This "safety cut rope axe man" is supposedly the origin of the term SCRAM for an emergency shutdown procedure.
Color coding
Telephone wires erupt in a multicolor cascade in a ground-level, pedestal-type splice case on a city street.
Dividing the set of 10 colors into two contrasting groups of 5 allows for exactly 25 combinations with one color from each group; thus, each pair in a bundle can be uniquely colored. A similar color code is applied to the ribbons that bind together all the pairs in a bundle, and to those of the superbundles. The result is highly festive! A specific wire might be identified as the blue-red conductor within the orange-black bundle within the brown-yellow superbundle.
Adding is favoured over subtracting in problem solving
How would you change this structure so that you could put a masonry brick on top of it without crushing the figurine, bearing in mind that each block added costs 10 cents? If you are like most participants in a study reported by Adams et al. in Nature, you would add pillars to better support the roof. But a simpler (and cheaper) solution would be to remove the existing pillar, and let the roof simply rest on the base.
A series of problem-solving experiments reveal that people are more likely to consider solutions that add features than solutions that remove them, even when removing features is more efficient.