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Quick dot product question

  1. Sep 8, 2005 #1
    What is the dot product of a unit vector (e) with a non-unit vector (A)? Is this some sort of identity?

  2. jcsd
  3. Sep 8, 2005 #2
    Let a be a unit vector and b be another vector. a * b = |a||b|cosθ. Since a is a unit vector, this becomes a * b = |b|cosθ. I believe that without more information, this is as far as it can be simplified.
  4. Sep 9, 2005 #3


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    \hat e\cdot\vec A[/tex] is the component of [tex]\vec A[/tex] along the [tex]\hat e [/tex]-direction.
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