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Best answer by ValeryOchkov

UK Mathcad Prime Minister is one user of our site about rockets calculation

See please more David Cameron watched Tim Peake's space launch and everyone's laughing at him - Mirror Online

DC-Rocket.png

10 replies

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24-Ruby IV
ValeryOchkov24-Ruby IVAuthor
24-Ruby IV
October 18, 2015

Three stage rocket:

9-40-Rocket-3.png

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    Raiko17-Peridot
    17-Peridot
    October 19, 2015

    Hello Valery,

    technically the Soyuz is a two-and-a-half (2 1/2) stages rocket as the four boosters start together with the core stage which continues running after the booster have separated. 🙂

    Raiko

    V
    24-Ruby IV
    ValeryOchkov24-Ruby IVAuthor
    24-Ruby IV
    October 19, 2015

    Tanks, Raiko, I Know it. See please - Союз (ракета-носитель) — Википедия

    I would like to solve this task with Союз with my students - see Московский лицей 1502. Класс 10-10

    Can you help us? With Alvaro and... Isaak!

    It is very interesting optimization problem. What is an objective function?!

    PS

    g=g(h(t), altitude)

    See please my Mathcad Web-sheet http://twt.mpei.ac.ru/MCS/Worksheets/g-h-psi.xmcd

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    AlvaroDíaz12-Amethyst
    12-Amethyst
    October 19, 2015

    Hi Vallery. Nice example. I guess that what you can remark there is that the equation Force = mass x acceleration isn't true!. Newton equation is Force = dp/dt.

    V
    24-Ruby IV
    ValeryOchkov24-Ruby IVAuthor
    24-Ruby IV
    October 19, 2015

    AlvaroDíaz wrote:

    Hi Vallery. Nice example. I guess that what you can remark there is that the equation Force = mass x acceleration isn't true!. Newton equation is Force = dp/dt.

    Thanks, Alvaro.

    See please One Rocket (пуск ракеты с подводной лодки)

    sok-g.png

    sok-wolfram.png

    A
    AlvaroDíaz12-Amethyst
    12-Amethyst
    October 19, 2015

    Hi Valery. Hope this helps.

    Best regards.

    rocket.gif

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    AlvaroDíaz12-Amethyst
    12-Amethyst
    October 24, 2015

    Well, attached my solutions.

    Results agrees with Un cohete de empuje constante (pages uses java, chrome don't support java), but there g=0. About original Valery question, "which's the target" for optimize the rocket, I guess that he want the "perfect" rocket, avaible in the same web: El cohete "perfecto"

    Best regards.

    V
    24-Ruby IV
    ValeryOchkov24-Ruby IVAuthor
    24-Ruby IV
    October 25, 2015

    9-37-F-m-a.png

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    AlvaroDíaz12-Amethyst
    12-Amethyst
    October 25, 2015

    Hi Valery. As usual, you're right. First solution gives the correct h,v. But, can you deduce from there the kinetics energy, for example? My point is that the relation F = - u*dm/dt gives the correct understanding, and the correct generalization for the Newton law F = dp/dt.

    rocketjpg_Page1.jpg

    Best regards.

    R
    Raiko17-Peridot
    17-Peridot
    October 26, 2015

    Hello Valery,

    I have problems replicating your first equation in Mathcad 15. I got rid of the units by using UnitsOf(xyz) but still it doesn't compute. any advice what I'm doing wrong apart from not working enough with ODEs?

    Raiko

    Sorry, I forgot to add the sheet

    V
    24-Ruby IV
    ValeryOchkov24-Ruby IVAuthor
    24-Ruby IV
    October 26, 2015

    Please

    rocket-ODE.png

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      24-Ruby IV
      ValeryOchkov24-Ruby IVAuthor
      24-Ruby IV
      October 27, 2015

      With friction, one stage rocket (please see the picture and Mathcad 15 - Mathcad Prime sheets in attch)

      Rocket-One-Friction.png

      D
      DenisJaunin15-Moonstone
      15-Moonstone
      October 27, 2015

      Hello

      This is just for information.

      Kind regards.

      Denis.

      http://www.maplesoft.com/products/maplesim/modelgallery/detail.aspx?id=151

      http://www.maplesoft.com/applicationbriefs/rocket.aspx

      V
      24-Ruby IV
      ValeryOchkov24-Ruby IVAuthor
      24-Ruby IV
      October 27, 2015

      Thanks, Денис, for links.

      But my students need in first line not descriptions but how we can use math soft (Mathcad or Russian clone SMath) for some math problems... In absolute simple form...

      I have had contacts with MapleSoft.

      One result

      Chemical Kinetics with Mathcad and Maple | Viktor Korobov | Springer

      A
      asokolov1-Visitor
      1-Visitor
      October 31, 2015

      The movement of the meteorite in the Earth's atmosphere with a view of the ablation

      Безымянный.png

      Meteor.png

      It is interesting to note the sharp braking and intense pulsed energy of the meteoroid at low altitudes, as well as the trajectory in the final phase of flight.

        V
        24-Ruby IV
        ValeryOchkov24-Ruby IVAuthor
        24-Ruby IV
        October 31, 2015

        Fine!

        Will be good to show one-two plots:

        bol.png

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          asokolov1-Visitor
          1-Visitor
          October 31, 2015

          Thank you!

          In my opinion, the most interesting are the destructive shock acceleration (~70g!)...

          Ускорение.png

          powerful thermal flash (10GW!) and a sharp decrease in weight...

          Flash.png

          mass.png

          and a significant change in the trajectory at the end of the flight

          trajector.png

          Slow meteors. Frames with an interval of 10 seconds:

          Video Link : 6493

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            asokolov1-Visitor
            1-Visitor
            November 1, 2015

            Unfortunately, Valery, the calculation is wrong - theoretical physicists in this film certainly take into account the effects of special relativity, mass at such speeds will change significantly and the relative velocity, too

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            24-Ruby IV
            ValeryOchkov24-Ruby IVAuthor
            24-Ruby IV
            November 1, 2015

            Alex Sokolov wrote:

            Unfortunately, Valery, the calculation is wrong - theoretical physicists in this film certainly take into account the effects of special relativity, mass at such speeds will change significantly and the relative velocity, too.

            Thanks, I know it.

            Give please more correct calculations. With elements of Einstein theory.

            A
            asokolov1-Visitor
            1-Visitor
            November 1, 2015

            Формула Циолковского.png

            Формула Циолковского2.png

            sorry, but remaining calculations are too complex for me, besides no practical value, they do not have.

            V
            24-Ruby IV
            ValeryOchkov24-Ruby IVAuthorAnswer
            24-Ruby IV
            December 15, 2015

            UK Mathcad Prime Minister is one user of our site about rockets calculation

            See please more David Cameron watched Tim Peake's space launch and everyone's laughing at him - Mirror Online

            DC-Rocket.png

            V
            24-Ruby IV
            ValeryOchkov24-Ruby IVAuthor
            24-Ruby IV
            February 22, 2016

            One question

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            asokolov1-Visitor
            1-Visitor
            February 22, 2016

            Не совсем понятно. Последнее выражение это v(t) в сокращенной записи. (а не y(x))

            V
            24-Ruby IV
            ValeryOchkov24-Ruby IVAuthor
            24-Ruby IV
            February 22, 2016

            An article for the journal "IT in school" - see please the attach.

            Can somebody to translate it into English?

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            24-Ruby IV
            ValeryOchkov24-Ruby IVAuthor
            24-Ruby IV
            April 10, 2020

            One fine manual solution

            Rocket.png

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