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Cross product

  1. Feb 17, 2016 #1
    In the cross product, why is vectorA*B=-(vectorB*A)
    How does the right-hand rule apply to this formula?
  2. jcsd
  3. Feb 18, 2016 #2


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    images?q=tbn:ANd9GcSYKSrl5ft_tg3ul7lg-nng6l3E8DPqJ7qlVL7Bif1vmCg-GMO1sg.jpg Look at the picture. If you rotate A towards B, the right-hand rule points upwards. If you rotate B towards A, the fingers point the opposite way, so the right-hand rule points downwards.
  4. Feb 18, 2016 #3


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    Apply the definition of cross product

    What happens to the direction of a x b when you rotate the hand to swap the directions of a and b ?
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