Feet in the Air

By now we have hopefully acquired the mindset needed for successfully troubleshooting switching power supplies. It is now time to start diving deep into technical details, because that is where the devil really lies. Power supplies are nothing if not all about seemingly minor details. Though that fact itself is a detail a lot of people miss, especially from 30,000 feet in the air ... 

The rate is about 146.67 feet per second. Substituting all the information into the formula for the height, s = -16(5)2 + 146.67(5) + 30 = -400 + 733.35 + 30 = 363.35 feet. After 5 seconds, the ball is 363.35 feet in the air. In case you ve ever considered taking calculus, here s some further encouragement. In this problem, calculus tells you that this ball is on its way back down after reaching its highest point when t was equal to about 4.5 seconds. Now, don t you want to know more — and what else calculus can do for you ... 

It lit the night sky like... a volcano, all the hot and molten lava in the sky... like an oil well on fire... nothing but fire above you. It went over a hundred feet in the air above my location, burning the whole time. It lasted not even a minute but it seemed to last forever. Scared the hell out of me 58... 

I run down stairs and make a peanut-butter and jelly sandwhich and go outside. At first the creature is startled by my sudden presence, but then he sees what I have in my hand. He comes running towards my hand, but then I realize he wants the sandwhich. I give it to him and he throws it about twenty feet in the air, and catches it in his mouth and swallows. 

As electronic instruments for navigation developed, it became possible to get more and more precise electronic fixes on exactly where an airliner was, moment by moment. You could know that you were over a certain city, what the distance to your destination was, and so on. Current satellite navigation systems allow you to know your position anywhere in the country to within fifty feet. Added to this were electronic systems that allowed a pilot to land blind when fog or other conditions made it impossible to see the runway. Electronic beacons allowed a precise fix how far you were from each side and each end of the runway, how many feet in the air you were, and the like. 

The thiamin deficiency that occurs with chronic consumption of raw fish results from the activity of thiaminase. Thiarriinase catalyzes the cleavage and thus destruction of the vitamin. The thiaminase content of various types of raw seafood has been measured (Hilker and Peters, 1966). Unfortunately, a reliable study of thiaminase in raw seafood is not yet available. Bracken ferns also contain thiaminase. Grazing animals such as sheep consume these ferns and develop thiamin deficiency. The deficiency results in brain lesiorrs in the animal and in the bending backward of the neck. Australians call this phenomenon "stargazing," The animal falls to the ground and pedals its feet in the air. 

Six months into the two-year project, one of the major subcontractors responsible for multistory steel-beam erection had employees working over 30 feet in the air without fall protection. After the second observation of this violation, the plant safety manager ordered the workers down, informed the contractor of the repeat violation, and initiated the process to terminate the contract. The contractor was removed from the project and replaced by a firm that accomplished all the goals initially established by the textile manufacturer. The plant manager in this scenario did not compromise. As a result, the project was completed on time with only one OSHA-recordable injury. 

The cockpit voice record stopped just before landing, for reasons unknown the official report merely notes that it ceased to function when the aircraft was about 30 feet in the air and on its landing approach. Thereafter, the only known communications are exchanges with the control tower. 

Oxygen used for eombustion oeeurs in the atmosphere. The ehemieal eomposition of air is approximately 21% oxygen and 79% nitrogen, or one part oxygen to four parts nitrogen. In other words, for eaeh eubie foot of oxygen eontained in the air, there are about four eubie feet of nitrogen. 

Despite the general availability of unlimited quantities of oxygen in the air, tremendous quantities of the pure gas are prepared annually for industrial and medical use. Billions of cubic feet of oxygen gas are manufactured every year, by liquefaction of air followed by fractional distillation to separate it from nitrogen. 

Soddy was fond of this rhetorical flourish and frequently advanced his own figures about radium/coal equivalents. Weart notes that Crookes claimed in 1903 the energy locked within one gram of radium, he calculated, could hoist the entire [British Navy] fleet several thousand feet into the air (Weart 1988, 25). 

The two plants that seem to be the best bet for ridding one s home of such chemicals are ferns and palms. These plants release moisture as part of photosynthesis and, as they do, pull chemicals from the air into their leaves. Even NASA has conducted some greenhouse experiments for long-term space exploration. Within hours, their plants [palms] had removed almost all traces of formaldehyde in the room. Both species of plants are ancient, dating back more than a hundred million years. Another trait they share is that they both live long lives, 100 years or more. This we expect from trees, but ferns and palms are plants plants that can grow to 65 feet in the proper setting Even their individual leaves live for one to two years [ferns] and one to nine years [palms]. Perhaps it is their primal qualities that have contributed to their ability to purify their environment. 

For rats and mice, the animal is either grasped by its tail and flipped in the air or held upside down and allowed to drop (2 ft above the cart surface) so that it turns head over heels. The normal animal should land squarely on its feet. If it lands on its side, score 1 point if on its back score 2 points. Repeat 4 times and record its total score. For a rabbit, when placed on its side on the cart, does the animal regain its feet without noticeable difficulty ... 

The interior volume of the theater, estimated from illustrations, was probably less than three hundred thousand cubic feet, i.e., about 10,000 cubic meters. Based on doses used for anesthesia, a concentration of as little as 2-3 mg per cubic meter of a super-potent Fentanyl derivative might be sufficient for a building that size, if instantaneous incapacitation is not required. This assumes continuous inhalation for about 30 minutes. Thus, if evenly distributed, the total amount of drug required might be in the range of a few dozen grams - almost certainly less than a pound. If the Russian authority pumped in 5x the effective dose (as it claimed), its uneven distribution in the air would likely have caused many deaths. But only one in six died. 

First you place your hand in the air and watch a piece of the palm seem to disappear (Fig. 6.1). Next, you leap two feet into the air and are pulled back down by the chain. 

Several feet away are some undulating pumpkins. Well, not pumpkins exactly, but close enough. As you walk you see glass, metal, and concrete structures—all in strange polyhedral shapes, like large, twinkling stars. A few greenish, frilly objects float in the air (Fig. 6.2). Plants ... 

The Problem How high is a baseball 5 seconds after it s hurled straight up into the air by a pitching machine if the ball is, at first, traveling at 100 mph and the pitching machine is sitting on the top of a building 30 feet up in the air ... 

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