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Homework Help: Which to use->Dot or cross product

  1. May 28, 2005 #1
    a crate is sliding (disregard friction) with d=(-3.0 m)i while a steady wind pushes against the crate F=(2.0 N)i + (-6.0 N)j

    How much work is done by the wind on the crate?

    Ok W=Fd so I want to multiply the two vectors together.

    [(-3.0 N)i ]*[(2.0 N)i + (-6.0 N)j ]

    Do I use a cross product or a dot product? Why?
     
  2. jcsd
  3. May 28, 2005 #2
    The answer is in the proper defining equation of work.
     
  4. May 28, 2005 #3
    D'OH

    Working on homework on the weekends again...

    :zzz:

    Thanks!
     
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