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Model Rocket Physic Equations

  1. Oct 4, 2005 #1
    below are my posts on my homemade RPG i was planning, after endless disagreement for help because of the exploding part i have subsided to a normal model rocket, seeing as how i bought a d-class rocket engine anyway. so, I would just like some certain equations that would help me in my launch, such as y(time or anything of that matter) x(weight) = z(whatever it would equal.) I'm hoping to recieve help this time and will keep you updated on the project.

  2. jcsd
  3. Oct 4, 2005 #2

    Tom Mattson

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    OK, I'm game. First of all a couple of questions:

    * What's your math and physics background?
    * Do you have any technical data on the D Class Engine (burn time, thrust, etc?)

    If you can't answer the second one then I'll do a little digging with the help of Google.
  4. Oct 4, 2005 #3
    thanks for your future help

    for your question one, i have no physics background, but i tend to catch on to math very easily, if i was given the equations i could do it and if i didn't understand something i can take the equation to my math teacher or science teacher.

    for the second question i have tried to dig information but it was extremely late and i was unsuccessful, i will try again later but it would be nice if you found something i didn't.
  5. Oct 4, 2005 #4

    Tom Mattson

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    OK, I think we're in good shape with the tech data. Check out this website:


    If you click on "Rocket Motors" and then on "Estes" we find the following:

    http://www.apogeerockets.com/Estes_Items.asp [Broken]

    I'm guessing that the D class engines are the ones that start with "D" (D12-0, D12-3, etc). They give exactly the info that I was looking for, and more (thrust, burn time, mass, impulse, etc).

    So let me ask another question: What is the exact make and model of your engine? This will become important when we come to putting numbers into equations.
    Last edited by a moderator: May 2, 2017
  6. Oct 4, 2005 #5

    Tom Mattson

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  7. Oct 4, 2005 #6
    i bought a 3 pack of d12-5 rocket engines at hobby world. I hope that helps for the equations.
  8. Oct 4, 2005 #7

    Tom Mattson

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    Before I get to the equations I need to know how far you've gone. So, which of the following do you know?

    * Algebra
    * Geometry
    * Trigonometry
    * Calculus

    It does help, because now I know to use the data for that engine.

    More tomorrow...
  9. Oct 4, 2005 #8
    I have done all those types of math aside from calculus. I'm predicting that i will learn it in a short period of time, its inevitable to happen in my grade.

    and yeah, i saw on that like, d = impusle, 12 = average thrust in newtons and 5 would = the time delay. i hope we get this on the go soon and when it is finally time to launch ill video tape it then post on a video blog site.
    Last edited by a moderator: Oct 5, 2005
  10. Oct 4, 2005 #9

    They way I figure it is, if the rocket flys, we know the original build and can modify it with other things... Camera, parachute ect.. :wink:

    And any non-idiot teachers can help if we really need it. A30 trig is tought heh.
    Last edited: Oct 4, 2005
  11. Oct 4, 2005 #10
    ok, it may seem as though this conversation is between tom mattson and I, that doesn't mean all...oohh...126 or so of you who have viewed this thread cannot intervene and help out.
  12. Oct 5, 2005 #11
    I posted some pictures of my RPG plans, but i guess they deleted them, whatever.
  13. May 23, 2009 #12
    hey im just reading your thread and its kinda funny i was just launching model rockets off for my physics class today didnt go so well... but my rocket did blow up, that was kinda cool
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