Intro: Parabola Plotting Web Pages
Graphics have become more available on web pages. A web page that can design parabolas can show what is now available.
Different applications require parabolas having different focal points. A parabola follows the following equation.
Y = X^2/(4*focal)
The old camera flash bulbs appeared to use a short focal length when compared to its radius. When the focal is 0.25, then Y will be unity when X is unity.
The web page to do this is only a text file. Feel free to save it as source on you computer.
Solar application may need a long focal length. If the focal is 1, then Y will be 0.25 when X is one. The radius of the parabola can be thought of as being X. The depth of the parabola can be thought of as being Y.
Some applications may require the focal point to be close to one half the depth. Using a focal which is at sqrt(1/8) will do the job.
The new graphing feature can be extended such that a web page can print out the segments of a parabola. The web page that does this is only a text file. Select a focal and whether to plot segments or the sides. Feel free to save this page on your computer. Look at the page's text.
The parabola is design to step X from 0 to 1 in 0.1 units. The side view plots both the X steps and the corresponding Y steps as lines. This web page should be printable on a single sheet of page. Or it can be saved as a pdf file to be printed later.
Half of a parabola can be constructed by printing out six segments and a left and right side.
The lines on the half parabola show how well all the X and Y dimension line up.
The plots are 700x700 bitmaps which avoid the auto scaling features found in most plotting resources. The plot will define a segment shape from a input a focal length which is relative to the parabola's radius. By importing these plots into a graphic application for scaling, it should be possible to construct any type of parabola desired.