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Homework Help: 3-angular momentum : independent of pivot?

  1. Dec 3, 2014 #1
    1. The problem statement, all variables and given/known data

    (i) Prove that dL/dt = 0
    (ii) Find the relation between space part and 3-angular momentum vector
    (iii)Show that 3-angularmomentum vector is independent of pivot


    2qvw9xx.png

    2. Relevant equations


    3. The attempt at a solution

    I'm not sure what part (iii) is trying to get at, but I think I've solved (i) and (ii):

    Part(i)
    [tex]\frac{\partial L^{ab}}{\partial \tau} = P^b \frac{\partial X^a}{\partial \tau} - P^a \frac{\partial X^b}{\partial \tau}[/tex]

    [tex] = \frac{P^bP^a}{m_0} - \frac{P^aP^b}{m_0} =0 [/tex]

    Part(ii)
    [tex]L_i = x_jp_k - x_kp_j [/tex]
     
  2. jcsd
  3. Dec 3, 2014 #2
    Solved it, thanks!
     
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