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24-Ruby IV
May 14, 2021
Question

Parabola and catenary

  • May 14, 2021
  • 3 replies
  • 4445 views

There are three random points on the plane through which an arc of a parabola and a similar arc of a catenary pass. What is the probability that the length of the parabola's arc will be greater than the length of the catenary's arc??

Catenary-Parabola.png

3 replies

23-Emerald I
May 14, 2021

Since a catenary describes a condition of minimum potential energy, I would guess that the probability is quite low.

23-Emerald IV
May 14, 2021

About 20...25 %.

First run over 100 iterationsFirst run over 100 iterations

No, it's more towards 30 %. The next run is over 200 iterations:

LM_20210514_CatenaryParabole200.gif

And finally over 1000 iterations, but showing only 1 in 5:

LM_20210514_CatenaryParabole1000.gif

Luc

24-Ruby IV
May 14, 2021

Is this a new math constant?

 

23-Emerald IV
May 14, 2021

No, it's not trial and error. I have an algorithm (a simple formula) that spits out a single set of guess values, with a success rate of over 99 % (that using those guess values, the solve block will find the catenary function parameters. If you look carefully at the animations, you can see the miss shots every now and then...).

That's better than a Covid19 vaccine...

 

Luc

24-Ruby IV
May 15, 2021

000100000100010000-0000011010000-00---110000100010000100-011001-0101101-01100000--1101--110101-010-010000101-001-010-0-0001-1-00000--0-10011101000-0-0-00-01010000-0-01-10-0001000-010100-0-00001101011100000110110111--0101-01-101010---000000001000100-000001100111000-10 (Tomorrow I will continue my research)

1 - Sc > Sp

0 - Sc < Sp

- (hiccup) - no solution

* - Sc = Sp (I am waiting for)

It's like a hiccup. You don't know when you will hiccup next time - when next time there will be no solution of the problem of catenaries and parabolas.
By the way, there is a very interesting study of the frequency and strength (- or ---) of hiccups.

24-Ruby IV
May 18, 2021

Catenary longer than a parabola about (a bit more) in 26 cases out of a hundred.

p-c.png

24-Ruby IV
May 18, 2021