What Does Pi Mean To You?

Discussion in 'Education & Learning' started by Von Jones, Mar 14, 2018.

  1. Von Jones

    Von Jones Supreme Member
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    Google displays notable events on it's homepage and today it is the 30th anniversary of Pi Day. Of course being the curious person I am I took a bite and began to read what Pi Day is. It's math and too technical for me to grasp any understanding of it. I've dreaded any math past algebra.

    I suspect there is someone who has an interest in Pi or knows someone who is.
     
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  2. Sheldon Scott

    Sheldon Scott Supreme Member
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    Pi, 3.14..... is an essential number for calculating many components of a circle. I used it a lot during my working years but I seem to have forgotten much.
     
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  3. Von Jones

    Von Jones Supreme Member
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    Good morning. So what kind of work did you use it for?
     
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  4. Sheldon Scott

    Sheldon Scott Supreme Member
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    I was a tool and die maker for 40 years. We used plane geometry and trigonometry a lot to set up and machine parts.
     
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  5. Shirley Martin

    Shirley Martin Supreme Member
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    What Does Pi Mean To You?

    It means that I am not so smart. I looked it up and I can't make heads or tails of it. :oops:
     
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  6. Bill Boggs

    Bill Boggs Supreme Member
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    As long ago as it has been I can stll remember secretly being happing I learned and understood how dto use Pi. I didn't know they hada pie day, but i sremember using Pi while working for Halliburton furgueing how much cement would be needed to plug a hole.We didn't have calculators back then as we have today. We used a slide rule. Those who used a slide rule everyday could use one about as fast as a daily user of the calculator today. I was not so fast.
     
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  7. Don Alaska

    Don Alaska Supreme Member
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    Wow! Somebody who remembers slide rules!! If I recall, slide rules had Pi marked on them to be used for disks, circles and cylinders--anything involve a round object.
     
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  8. Chrissy Cross

    Chrissy Cross Supreme Member
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    I learned about Pi in grade school @Shirley Martin! Also, love your hat! Classy lady!

    @Von Jones ...Happy belated Birthday! :)
     
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  9. Frank Sanoica

    Frank Sanoica Supreme Member
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    @Don Alaska
    Attending DeVry Technical Institute in 1961-'63, tiny calculators were still only a gleam in someone's eye. We all carried sliderules having a huge number of different scales on them. I recall conversion of imaginary numbers (used a LOT in Electrical Engineering) to Polar form, and back again, as pretty daunting effort! Working with Vector quantities necessitated doing this, as multiplying and adding them is facilitated by use of both forms.

    Slide rules worked, in general, by taking advantage of exponents: multiplying numbers is accomplished by adding exponents, thus the "lengths" of the scales were added to one another to reach the answer (often the WRONG one). Frank
     
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  10. Von Jones

    Von Jones Supreme Member
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    Thanks Chrissy.
     
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  11. Von Jones

    Von Jones Supreme Member
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    Neither could I.
     
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  12. Frank Sanoica

    Frank Sanoica Supreme Member
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    Even more difficult to grasp is the use of Pi as it applies to all things which rotate, spinning around, like car engines, gears, and the like. In Electrical Engineering, Pi is taken to a more useable level, by incorporating Imaginary Numbers, if you can imagine it! What can an imaginary number possibly be? Gotta recall what squares and square roots are, square root of 4 = 2, for example. Square root of 1 = 1, since 1X1=1. Ah, but what about Square Root of Negative 1, or -1? Problem is -1 X -1 = +1, so, it can't work. Thus, the "imaginary number" is the Square Root of -1, called "i" in mathematics.

    Enter the next foible: "I" or "i" was already allocated in E.E. as Current, Amperes, so the controversy was solved by using "j" instead of "i". The basic form of the Imaginary Number is written as " (a + bi) ", or, (a + bj), where a and b are everyday numbers we all know about. So, 2 + 2i might be an example of an imaginary number.

    Graphically, the "2" would lie on the X-axis, horizontally, while the "2i" would lie verticaly on the Y-axis. Resolving them to form a single line which becomes the Hypotenuse of two triangles, results in a Vector lying at a 45 degree angle, and having the absolute value of 2 X Square Root of 2, or 2.828 approximately. That vector, 2.828 /_ 45 is part of a whole 'nuther system called "Polar Coordinates". We had to work those things back and forth using slide rules, pencil, and paper.

    Any wonder why I'm "half-nuts"?
    Frank
     
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  13. Don Alaska

    Don Alaska Supreme Member
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    What happened to e (~2.718)? I guess we need a slide rule in natural logs as well as base 10.
     
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  14. Frank Sanoica

    Frank Sanoica Supreme Member
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    @Don Alaska
    My slide rule had about 8 scales, including both logarithm bases, even had Hyperbolic Trig functions!

    Base e has some mystical qualities, for me anyhow. e raised to any power <1 is a negative fraction between - infinity and 1, e to the zero = 1, of course, and if I recall correctly the Derivative of e is = e, as is the integral of e.
    Frank
     
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  15. Bobby Cole

    Bobby Cole Supreme Member
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    @Von Jones had a birthday recently? OOPS! Instead of cake maybe I can send her a pi.....................Happy Birthday !!!!
     
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