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Principia confusing sentence. Please make is simpler!

  1. Jan 6, 2012 #1
    Can someone please help me understand what this means?:

    "And therefore if weight 'p' is to weight 'A' in a ratio compounded of the reciprocal ratio of the least distances of the chords PN, AM, from the center of the wheel, and of the direct ratio of pH to pN, the weights will have the same effect towards moving the wheel and will therefore sustain each other."

    I am totally confused.

    Tell me if this is insufficient to answer my question.

    Thanks for any responses.
  2. jcsd
  3. Jan 7, 2012 #2
    Looks like he's just talking about torques.
  4. Jan 7, 2012 #3
    People have to see the diagram to follow what's being said, but it actually very trivial. Look at the diagram when he says "a ratio compounded of the reciprocal ratio of the least distances of the chords". Old English sucks but the ratio is the weights p and A. The "chords" are the distances from pivot point at O. "Compounded of the reciprocal ratio" refers to the effects the chord lengths has on the weights relative torque.

    It's really a mess but if you look at the picture and understand that O is a pivot point with weights hanging from the chords at some distance, and understand the forces it entails at various points, then it's obvious a lot of words was thrown at very little.
  5. Jan 7, 2012 #4
    Ok, thanks guys. Even if I dont understand every last detail, I understand the broad idea of what he is talking about
  6. Jan 7, 2012 #5
    People still read the Principia?

    Well still better than reading the bible :)
  7. Jan 7, 2012 #6
    It sounds as though this was your first choice for a physics textbook, while this isn't why you made the thread I would suggest that you find something else. There are many books that will give you more information more clearly.
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