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Homework Help: Does Linear momentum operator and angular momentum operator

  1. Feb 10, 2010 #1
    1. The problem statement, all variables and given/known data
    Does Px Lx operators commute?

    2. Relevant equations
    This is just me wondering


    3. The attempt at a solution
    I tried doing this and I got something weird, my friend said that when you take a derviative with respect z or something that when you try to take the derivative of something that's not with respect to z it goes to 0. Is this true? p.s. im not very good at math.
     
  2. jcsd
  3. Feb 10, 2010 #2
    You tell me. L_x is made up of rs and ps. Which r and ps is L_x made of, and which r and ps does p_x commute with?
     
  4. Feb 10, 2010 #3
    [tex]\hat{\vec{L}} = \vec{r} \times \hat{\vec{p}}[/tex]

    [tex]\times[/tex] is the cross product...

    Do the math and then see if they commute

    ps
    [px , py] = [px , pz] = 0
     
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