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I Classical Mechanics Goldstein Eq3.14 help please

  1. Dec 7, 2017 #1
    how is md^2r/dt^2 . dr/dt = d/dt (1/2 m (dr/dt)^2 )

    Thank You
     
  2. jcsd
  3. Dec 7, 2017 #2

    PeroK

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    Chain rule.
     
  4. Dec 7, 2017 #3
    Can you work it out for me explicitly ?
     
  5. Dec 7, 2017 #4

    Ibix

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    Can you state the chain rule? Can you apply it to the time derivative of ##(dr/dt)^2##?
     
  6. Dec 7, 2017 #5

    PeroK

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  7. Dec 7, 2017 #6
    2dr/dt . . is that right ?
     
  8. Dec 7, 2017 #7
  9. Dec 7, 2017 #8

    PeroK

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    That makes no sense. The LHS is the answer to the derivative on the RHS. There's nothing to work out on the left.

    The stackexchange link I gave you is all about why that is not the answer!
     
  10. Dec 7, 2017 #9
    okay Got it. Thank you so much !!
     
  11. Dec 8, 2017 #10
    The rest of Goldstein may present difficulties.
     
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