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Homework Help: Curvature and Torsion

  1. Sep 27, 2011 #1
    1. The problem statement, all variables and given/known data

    http://www.mathhelpforum.com/math-help/attachments/f6/22423d1317129472-curvature-torsion-untitled.png [Broken]



    3. The attempt at a solution

    What I did was I calculated the unit vector for dN/ds={.21i+0.91j-0.42k}/ sqrt(.21^2+.91^2+0.42^2)=.205i+0.889j-.4102k


    then, I took a derivative of N

    since N=BxT,

    dN/ds=(dB/ds)xT+Bx(dT/ds)
    then taking T and doing dot product on both sides:
    T⋅(dN/ds)=T⋅(dB/ds)xT+Bx(dT/ds) which simplifies to:
    T⋅(dN/ds)=dB/ds
    T⋅(dN/ds)=-τN

    From here I have no clue what I should be doing..

    Any suggestions will be greatly appreciated
     
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Sep 27, 2011 #2
    nvm figured it out
     
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