What are Radians? Where Do They Come From?

Mathematics
Consider a simple equilateral triangle (a triangle that has 3 equal sides and 3 equal angles). Most high-school students know the three angles of such a triangle are 60 degrees (60°) each, for a total of 180°. But degrees is not the only unit used to quantify an angle. Alternately radians can be used. What are radians? Are they just another number? Where do they come from? Degrees Before we get into radians, however, let’s consider where degrees came from, and why it may not be the best choice for the measurement of an angle. If you are facing north and turn to the east, you have turned 90 degrees. Now turn south and you’ve turned another 90 degrees. Turn west, another 90 degrees. Continue the turn so you once…
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Quasi-Spherical Orbits – by Author Bob Chester

Mathematics
The Most Interesting Curves You've Never Heard Of by Robert G. Chester [caption id="attachment_13083" align="alignleft" width="340"] Author Robert G. Chester[/caption] Quick, what simple rotations simultaneously generate the circle, the parabola, and the intersection of a cylinder and a sphere? Can these rotations also subsume the hippopede of Eudoxus [1], the limaçon [2], Viviani’s curve [3], rhodonea [4], the lemniscate of Gerono [5], and Fuller’s “great circle railroad tracks of energy” [6]? Quasi-Spherical Orbits, or QSOs, are the dynamic three-dimensional curves that result when a point rotates simultaneously about two or more axes. These intriguing curves provide insights and yield results in mathematics and physics alike. Viviani's Curve [caption id="attachment_13087" align="alignleft" width="133"] Rotation a[/caption] A point rotates in the right hand direction around the z-axis. The orbit is a circle in…
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Understanding the Spherical Polar Coordinate System

Mathematics
[caption id="attachment_9496" align="alignright" width="480"] A cone in the spherical polar coordinate system. CC-SA 3.0 Unported by Lantonov[/caption] Do you have a basic knowledge of the spherical polar coordinate system? A coordinate system provides a way to describe and plot math functions using two or three variables. If there are two variables the graph is 2D. If there are three variables, the graph is 3D. The Cartesian Coordinate System The most familiar coordinate system is the Cartesian coordinate system. Typical variable names are x and y in 2D (although variables can have any name), and x, y, and z in 3D. Every point of every 2D function has a unique value in (x, y). Every 3D function similarly has a unique value in (x, y, z). The Polar Coordinate System This…
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Collapsing then Expanding the Equation for a Sphere

Mathematics
[caption id="attachment_8626" align="alignright" width="480"] How simple is a sphere?[/caption] Equation for the Simplest Sphere The equation for a sphere with its center at the origin is: x2 + y2 + z2 = c2 Where c is a positive constant. For simplicity, let's choose a positive constant, k, such that k = c2. Equation for a Circle by Collapsing a Sphere Collapsing it in one dimension generates the equation of one of three circles: x2 + y2 = k x2 + z2 = k y2 + z2 = k Equation for a Point by Collapsing a Circle Collapsing the three circles in one dimension generates two equations representing precisely two points for each of them: For x2 + y2 = k, x²2 = k y2 = k For x2 + z2…
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Generate 2D Math Objects by Collapsing 3D Math Objects

Mathematics
I had some excellent high school mathematics instructors. They both loved their field and took an interest in their students. Since high school, I have had a deep interest in collapsing 3D mathematical equations to derive equations for 2D mathematical objects or modifying 2D objects into other 2D, or 2D objects into 1D. A 3D sphere becomes a 2D circle. A 2D parabola becomes a 1D line. The 2D hyperbola shown, if collapsed along the x-axis, becomes two 1D line segments stretching at one end to infinity. The same hyperbola collapsed along the y-axis becomes a complete line. A 2D circle becomes a single 1D line segment of a length equal to the diameter. An Example of Collapsing 3D into 2D What can be obtained by collapsing 3D math objects…
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Mathematical Equation for a Cone

Mathematics
You go to the mall and request a double scoop of Rocky Road ice cream. The fellow serving says "Yes," and then he asks you asks if you would like that on a wafer or a sugar cone? Since most have eaten ice cream since childhood (unless we are dairy or otherwise intolerant), the majority of people think of a simple v-shape hollow structure as a cone. It has a top. It has a bottom. But is this the kind of geometrical shape that mathematicians think of when they refer to deriving the mathematical equation of a cone? A Mathematics Cone The cone of the mathematician bears some resemblance to that, but there are differences. The figure included with this article demonstrates that there are two v-shaped portions, not one.…
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Not Infinitesimal Point Coordinates

Mathematics
[caption id="attachment_7388" align="alignright" width="480"] A coordinate system.[/caption] Infinitesimal point coordinates or not? Do you occasionally enjoy speculating? Even if one has technical training, if he speculates outside his field of expertise, he is opening himself up for possible difficulty. What he speculates, if he voices it, could result in his being labeled someone who doesn’t know what he is talking about. But I never was bright enough to avoid speculation, though I always acknowledge it for what it is. So humor me here… So if you know something of all this and what I'm writing either doesn't jive, or you can 'supercharge' it, please let me know. Mathematicians’ Points – Reality? Generally, a point in space is seen as a dot in space, having infinitesimal point coordinates, that is, no…
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Is a Circle a Polygon or Not? Implications for Calculus

Mathematics
[caption id="attachment_16285" align="alignright" width="380"] A 12-sided dodecagon.[/caption] What do you think? Is the circle a polygon, or not? As a result of watching a child’s video, I previously wrote a brief piece about the “corners” of a circle. The video was designed to teach children the various shapes—how many sides does a shape have, and how many corners? The video maintained a circle has no corners. I called that into question. I still do. And yet, I do not. I now think it’s all in how you look at it. Or, you might say, it’s all in the mathematical perspective. Consider. The Circle by Definition One can define the two-dimensional circle as the complete collection or “set” of points equidistant from a set point, not part of the circle. In…
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Discrete Mathematics: What is a Point and What a Line?

Mathematics
[caption id="attachment_7234" align="alignright" width="440"] Discrete points? An abstract.[/caption] Most technically minded people will probably take me to task over what I am going to say in this article. That is OK, though. I’m used to it. Not only are my writings quirky—I am quirky. Hey! This is QuirkyScience. I want to talk about points and lines in the real world—in other words, discrete mathematics. What is Reality, What Fantasy? To a mathematician, the point may be a dimensionless object in 3D space, a mathematical object with an x, y, z coordinate in Euclidean space. A line would be a collection of such dimensionless points lined up all in a row. But that is in the world of the mathematician. In the real world, there can be no such thing. Rather,…
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Surface Area and Adsorption

Mathematics
[caption id="attachment_6504" align="alignright" width="480"] Activated Carbon - CC-2.5 by Ravedave[/caption] Surface area? What's that? And how does it affect physical properties? There are two similar words in the English language: absorption and adsorption. While they are related, they are at the same time distinctly separate. Absorption, simply put, is sucking into the interior or volume of something. Water, for instance, is sucked into the volume of a sponge. The water is held throughout the sponge. Adsorption Adsorption is a surface phenomenon. A substance that is adsorbed is adsorbed onto the surface. It does not enter into the interior or volume of the adsorbing agent. The difference in these physical processes determines the most efficient form the absorbing or adsorbing agent should assume. [caption id="attachment_15070" align="alignright" width="340"] Zeolite Materials for Methane…
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