Delauny Triangulation using footage shot in the Cuyamaca Mountains.
[quicktime]http://terezakis.org/itp/video/1.mov[/quicktime]
(here’s a link to a longer, larger file)
Amazed by Scott Garner’s Tri Me I looked at jsfeat and ran examples.
[quicktime]http://terezakis.org/itp/video/2.mov[/quicktime]
Thinking about the first experiment in Jeff Feddersen’s Sustainable Energy class, I repeated (though not exactly) an experiment of Michael Faraday’s originally conducted in 1831.
It was his observation that by varying a magnetic field over time, an electric field would be generated. This phenomenon came to be known as the law of (electromagnetic) induction. The two videos below use LEDs, a coil of wire, jumper wires, and a large magnet hanging on a string as a pendulum.[quicktime]http://www.terezakis.org/itp/video/led-double-4-blog.mov[/quicktime]
I have a few more eighteenth century concepts I would like to physically review in order to prepare for my midterm project.
I couldn’t quite do the math on the setup in the videos as I didn’t know the coil length. The voltage was pretty high – 7.5 – 8.1 Volts. As expected it was not enough power to be able to drive a small motor.
The next tests will use a capacitor.
[quicktime]http://www.terezakis.org/itp/video/led-strip.mov[/quicktime]
Peter Terezakis
ITP
Tisch School of the Arts
http://www.terezakis.com
Magnetic Fields
[cvg-video videoId=’2′ width=’480′ height=’360′ mode=’playlist’ /]
The NASA computer animation illustrates the Earth’s space storm shield in action and shows our planet’s magnetic fields as a dynamic system.
The solar wind, a thin, high-velocity electrified gas, or plasma, blows constantly from the Sun at an average speed of 250 miles per second (400 kilometers/sec). In the animation this is represented as a stream of yellow particles flowing from the Sun. The solar wind impacts the Earth’s magnetic field, represented by the blue lines. As the solar wind flows past the Earth’s magnetic field, it generates enormous electric currents that heat Earth’s space storm shield, which is a layer within the ionosphere (Earth’s electrically charged outer atmosphere). Satellite observation has shown that this causes electrically charged oxygen atoms (oxygen ions) to be ejected from the ionosphere into space.
The expelled oxygen ions are represented by the green particle streams. The ejected oxygen ions gain tremendous speed as they leave the atmosphere, become trapped by the Earth’s magnetic field and ultimately encircle the Earth, where they form a billion-degree plasma cloud around the planet, represented by the red cloud. The blue doughnut shape represents the high-speed flow of these particles around the Earth.
The red ‘ring of fire’ around the Earth’s polar regions represents the contribution of the particles to the aurora (the northern and southern lights).
This is part of the mechanism by which earth is constantly bombarded by charged particles from the sun as we travel through space and time. It’s as if we are living our our lives on a component of an electrostatic generator whose scale defies comprehension.
Peter Terezakis
ITP
Tisch School of the Arts
http://www.terezakis.com
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When Jeff Feddersen showed our class a demonstration of power generation, I was impressed by the visible effects of Lenz’s law when an electrical load was placed on the hand-cranked generator.
” Lenz’s law states that the current induced in a circuit due to a change in the magnetic field is so directed as to oppose the change in flux or to exert a mechanical force opposing the motion.” – Heinrich Lenz, 1834
We are surrounded by this effect – and the work that it does.
The past week I have reading and visualizing about the physics and models of magnetic waves, induction, electro-magnetic fields (EMF), magnetic moments, which brought me to Lenz’s law.
The subject is complex and filled with calculus the nuances of which are difficult to comprehend.
Looking at the “Cliff Notes” version, the concept is straight forward:
Field energy
The electric field stores energy. The energy density of the electric field is given by:
In general the incremental amount of work per unit volume δW needed to cause a small change of magnetic field δB is:
Conservation of momentum
Momentum must be conserved in the process, so if q_1 is pushed in one direction, then q_2 ought to be pushed in the other direction by the same force at the same time. However, the situation becomes more complicated when the finite speed of electromagnetic wave propagation is introduced (see retarded potential). This means that for a brief period of time, the total momentum of the two charges is not conserved, implying that the difference should be accounted for by momentum in the fields … Maxwell called this the “electromagnetic momentum” … Wikipedia .
Since taking apart my first motor to pull out the magnets when I was a child, to looking at motors today, every model that I have ever seen – in person or on paper – has either the magnet or the coil as a stationary object.
What if the magnetic resistance due to induction was allowed to self-optimize/be reduced within a given system? Aside from conserving momentum, would EMF be reduced, stay the same, or increase?
I’m thinking that I would like to design, construct, and analyze, an experiment and its outcome.
Peter Terezakis
ITP
Tisch School of the Arts
http://www.terezakis.com
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What if we think of our planet as a spherical capacitor?
 Two concentric plates, separatedby a dielectric, moving through the volume of space. |
Formula to determine the |
Using this model, earth ground would be our planet, the insulating dielectric would be the atmosphere, and the second capacitive component (plate) would be the ionosphere.
Capacitors often arc/leak/discharge on the work bench:
Which would mean that there should be a change in electrical potential as we leave earth ground/change observational altitude:
I know it’s more than a little whacky, and way over-simplified, but I keep thinking about the dynamic differences in electrical potential between moving bodies of air and earth ground as well as between the ionosphere and the earth.
I can’t help but wonder since there is enough electromotive force to operate an electroscope, bias a MOSFET, might there not be a way to construct an antenna to at least charge a battery, if not power a city, or the planet, using the power which surrounds us on a planetary and/or a cosmic scale?
If the answers to these questions were easy, or already out there, Big Oil would be out of business, and they are not.
The scale and scope of this line of thinking is mind-boggling and very interesting to me. There is a recurring common symmetry in Tesla’s drawings, NASA imagery, and models of basic physics which I find intellectually compelling and aesthetically satisfying. How cool would it be to continually charge super-capacitors through a system of antennas, powering our cities and our homes, by the EMF naturally generated by nature?
Peter Terezakis
ITP
Tisch School of the Arts
http://www.terezakis.com
Some batteries last longer than others. This one has been running since at least 1840, possibly fifteen years earlier.
More on the Oxford Electric Bell or Clarendon Dry Pile – one of the longest running science experiments in the world.
More on the battery:
Zamboni/Duluc Dry Pile
Interestingly, the Clarendon/Oxford Bell is a permutation of a Lightning Bell invented in 1742 and used by Ben Franklin in 1752.
“If we use fuel to get our power, we are living on our capital and exhausting it rapidly. This method is barbarous and wantonly wasteful and will have to be stopped in the interest of coming generations.” – Nikola Tesla, 1900
Please Enable Javascript for this <a href=”http://oilprice.com/Energy/Crude-Oil”>Crude Oil</a> widget to work
Between Tesla’s comment and the data in the widgets, we need to develop another method for supplying power to the world.
Peter Terezakis
Tisch School of the Arts
http://www.terezakis.com
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The class I am taking on Energy and Sustainability has given me occasion to rethink the cost upon our living planet in man’s pursuit of energy, and profit. With consciousness being the partial product of advertising, it is been difficult to imagine a world not run by the fossil fuel industry. What would our planet be like with out burning oil fields, exploding rail cars, vast open pit mines, drilling operations, and the infrastructure required to excavate, mine, transport, refine, distribute, meter, burn, carbon-based fuel let alone maintaining such a complex infrastructure?
Petroleum as a source of energy is a relatively recent arrival in the history of civilization. This doesn’t mean that it is here forever; that man and carbon fuels will be joined at the hip until the end of humanity; unless of course fossil fuel consumption ushers in that end.
From the early 1600’s, until shortly after the invention of kerosene, whale oil lit the lamps of America and Western Europe. Consumers also used the bone, fat, and meat, of whales to make soap, perfumes, hoops for dresses, shirt stays, and candles.
1846 was the peak the whaling industry was the fifth largest income producing industry in the United States economy. Coincidentally, it was also the year in which kerosene was discovered and the petroleum industry began.
In 1851 Herman Melville’s Moby Dick was published, six years past the whaling industry’s peak. By that time, kerosene had started to make inroads into the marketplace. The advent of less-expensive, more reliable petroleum technology eroded the need for rendered fat from whales to burn for light.
By 1861 America’s once valuable fleet of 640 whaling vessels were nearly worthless. Whaling ships were purchased by the Union Army, filled with granite, and strategically sunk in a failed attempt to blockade rivers during the American Civil war.
Before the end of the century, the whaling industry had declined by ninety percent, thanks to a still burgeoning petroleum technology and the discovery of plastics.
It may be difficult to imagine, but as the reigning technology of the day, no one thought whaling would lose its position in the marketplace:
“Great noise is made by many of the newspapers and thousands of the traders in the country about Lard oil, Chemical Oil, Camphene Oil, and a half dozen other luminous humbugs; and it has been confidently predicted by more than one astute prophet that the Sperm Oil trade would soon come to an end, and the whales be left in undisturbed possession of their abode . . . But let not our envious… hog-gish opponents, indulge themselves in any such dreams.” — From whale oil and beyond By Eric Jay Dolin That text sounds a lot like the gospel spouted by petroleum bloggers and pundits of today.
Today we have other sources of energy, fashion accessories, food, and and more, but the slaughter of whales continues.
The barbaric whaling video isn’t as much of a non sequitur as you might first think.
The deal is that the technology of petroleum will inevitably face the same fate as Ahab. The problem is that the new technologies for extracting petroleum products from the earth are equally murderous, barbaric and short-sighted.
Instead of poking harpoons into living breathing animals, we’re now doing the same to sections of the living earth which sustain us all. 97% of the water on our earth is undrinkable. After big capital has poisoned the aquifers, and solar or another technology has consumed the oil industry, Mobil, Shell, Exxon, and others will be selling you clean water to drink. If this sounds far-fetched, or paranoid, they are already in these industries.
Given what we know of whale oil, investing in fossil fuels today is analogous to investing in a dominant industry experiencing foundational cracks from the entry of new technology. What is worse is that fossil fuel companies are overvalued as they rely on “stranded assets;” carbon which will become unburnable for any of a number of reasons. This is going to result in a major loss of investment value for traditional producers.
Peter Terezakis
Tisch School of the Arts
http://www.terezakis.com
“The New Oil” • “The privatization of water““Water is too cheap.” • “Oil companies buy water rights”
THE SKY IS PINK by Josh Fox and the GASLAND Team from JFOX on Vimeo.
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