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Homework Help: Relative Motion

  1. Jun 12, 2007 #1

    Could somebody please give me clues as to how to do this problem?

    A ship cruises forward at vs = 4 relative to the water. On deck, a man walks diagonally toward the bow such that his path forms an angle delta = 28 degrees with a line perpendicular to the boat's direction of motion. He walks at vm = 2 m/s relative to the boat. At what speed does he walk relative to the water?

    Thank you!
  2. jcsd
  3. Jun 12, 2007 #2


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    [itex] \vec{v}_{mw} = \vec{v}_{ms} + \vec{v}_{sw} [/itex]
    where my notation is ms = man with respect to the ship, mw = man with respect to the water, etc.

    Just add the two vectors and find the magnitude of v_(mw)
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