Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Vector Cross Product

  1. Apr 9, 2008 #1
    If vectors V_1 and V_2 are perpendicular, lV_1 x V_2l =? I know that if they are parallel for vector cross product, they equal 0.
     
  2. jcsd
  3. Apr 9, 2008 #2

    mathman

    User Avatar
    Science Advisor

    The cross product is a vector perpendicular to V_1 and V_2. Also V_1 and V_2 don't have to be perpendicular to each other, only not parallel.

    Note that this only makes sense in 3 dimensional space.

    Further note: the magnitude is |V_1|x|V_2|cos(a), where a is the angle between the vectors. There is a sign ambiguity.
     
    Last edited: Apr 9, 2008
  4. Apr 9, 2008 #3

    ehj

    User Avatar

    Isn't it |V_1|*|V_2|*sin(a)?
     
  5. Apr 9, 2008 #4

    mathman

    User Avatar
    Science Advisor

    You're right - my bad.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook