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Newton's Principia Problem

  1. Jan 9, 2015 #1
    Hello everyone, I am reading Principia Lemma 10 and I cannot understand it. Can someone please help explaining? Thank you very much.
    Furthermore, is there any way of understanding the Principia in a more numerical ways rather than words like this? Just asking.
    Again, thank you very much.
  2. jcsd
  3. Jan 10, 2015 #2

    Doug Huffman

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    S. Chandrasekhar Newton's Principia for the Common Reader Chapter 3, Section 15, pp 50-52 in modern integral notation.
  4. Jan 10, 2015 #3

    Philip Wood

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    I think that in modern terms, this is [itex]s = \frac{1}{2} a t^2[/itex]. So [itex]\frac{s_1}{s_2} = (\frac{t_1}{t_2})^2[/itex]. This is constant acceleration from rest. Since it's at the very beginning off the motion, the force won't have had time to change?
    Last edited: Jan 10, 2015
  5. Jan 10, 2015 #4

    Stephen Tashi

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    It would interesting to know whether Newton is representing a graph of a function of position vs time with time on the y-axis or whether he is thinking of the curves as trajectories of an object in 2-D space.
  6. Jan 10, 2015 #5
    Wao, thank you everyone, this helps much
  7. Jan 11, 2015 #6


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    Staff: Mentor

    Last edited by a moderator: May 7, 2017
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