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Homework Help: Magnitude and Direction, Canoe on River

  1. Jan 1, 2013 #1
    1. The problem statement, all variables and given/known data
    A canoe has a velocity of 0.35 m/s southwest relative to the earth. The canoe is on a river that is flowing 0.65 m/s east relative to the earth. Find the velocity (magnitude and direction) of the canoe relative to the river.

    3. The attempt at a solution
    0.930985 is the magnitude.
    Then I have no clue how to get the angle in terms of counterclockwise from east.

    Thanks very much in advance!
     
    Last edited: Jan 1, 2013
  2. jcsd
  3. Jan 1, 2013 #2

    gneill

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    Staff: Mentor

    Hi ap_physics; Welcome to Physics Forums.

    How did you arrive at an angle of 315 degrees for the canoe's velocity? I would have thought that "southwest" would be halfway between south and west.

    Edit: I see you've edited your original so that the angles of the vectors are no longer shown. Perhaps you could just explain your approach to the problem?
     
  4. Jan 2, 2013 #3
    Well, I posted my attempt earlier, but it was wrong, and I was given the answer for the velocity by my teacher, as it was too complicated for our level. But, he says I can still find the angle. But, I don't know which formula to use.
     
  5. Jan 2, 2013 #4

    gneill

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    Staff: Mentor

    Okay, what have you learned so far about adding and subtracting vectors? Have you learned how to determine their angles from their x and y components?
     
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