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Homework Help: Physics: strange vector hw problem

  1. Sep 16, 2005 #1
    The minute hand on a watch is 2.0cm in length. What is the displacement vector of the tip of the minute hand?

    from 8-8:20 am.

    Express vector DeltaR in the form DeltaR_x, DeltaR_y, where the x and y components are separated by a comma.

    I thought i had it with the answer of 3.4 cm, but they want it in x and y components :confused: its a circle! My book has nothing for me and im significantly lost.
  2. jcsd
  3. Sep 16, 2005 #2
    The displacement vector points from the starting location to the final location, it is a straight line. It's just an arrow pointing from start to finish, break this vector into components.
  4. Sep 17, 2005 #3


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    Draw the displacement vector from the tip of the minute hand at 8:00 to the tip of the minute hand at 8:20.
  5. Sep 17, 2005 #4


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    Actually it might be simplest to do this in components. The "components" of the minute hand at 8:00 are easy. What angle does the minute hand make with the horizontal at 8:20? (Hint: the minute hand move 360 degrees in an your and 5 minutes is 5/60= 1/12 of an hour. How many degrees does the minute hand move in 5 minutes? Why is "5 minutes" important here?)
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