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Homework Help: Relative Velocity of a boat

  1. Oct 7, 2007 #1
    1. A boat, whose speed in still water is 2.20m/s, must cross a 260m wide river and arrive at a point 110m upstream from where it starts. To do so, the pilot must head the boat at a 45 degree upstream angle. What's the speed of the river's current?

    2. How do you incoporate 45 degrees into the work?

    3. So far, I have

    a^2+b^2=c^2
    c= sqrt(110^2+260^2)=282m
     
  2. jcsd
  3. Oct 7, 2007 #2

    Astronuc

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    The boats speed relative to the water is 2.2 m/s and it is pointing 45° with respect to the shoreline. So determine the speed in the direction of the other bank, or normal to the stream. Find the time it takes to go 260 m.

    With that time, determine the effective speed to up stream 110 m.
     
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