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Homework Help: Cross Product Fun

  1. Apr 19, 2008 #1
    1. The problem statement, all variables and given/known data

    1 [tex](H_1 - H_2) \times \hat n = J_s[/tex]
    2 [tex](H_1t - H_2t) = \hat n \times J_s[/tex]

    How does one get from the first statement to the second statement?

    3 [tex]H_{1t} - H_{2t} = J_s[/tex]

    This is causing an interesting problem when I plug in numbers, I would have just left it with statement (3) but if I do I get something completely different. My book gives (2) but doesn't explain how it derives it.
  2. jcsd
  3. Apr 19, 2008 #2


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    If the 't' means 'tangential' part use ax(bxc)=b(a.c)-c(a.b). The H part becomes H minus the normal component of H.
    Last edited: Apr 19, 2008
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