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Resultant Displacement with direction problem

  1. May 23, 2016 #1
    1. The problem statement, all variables and given/known data
    You run towards the west with a velocity of 4 m/s for 5 minutes. You then continue running to the northeast (halfway between north and east) at 2 m/s for 8 minutes. (a) At the end of the 13 minute run , what was your total running distance? (b) At the end of the 13 minute run, what was your resultant displacement relative to your starting position?

    2. Relevant equations

    3. The attempt at a solution
    i got the total distance by converting minutes into seconds and multiply the number by each velocity i got 2160m for total running distance. i was unable to figure out the resultant i created the triangle with using 45 degrees as the angle (due to the north east reference), but i am not getting the answers similar to the answer key

    i used the given numbers to find the vertical and horizontal components so i made my triangle with the 45 degree reference and 2m/s to find the horizontal and vertical components (i solved using trig) that did not due.

    i then tried using the numbers converted to seconds and that did not work either. So i used 960m/s to solve the triangle with the 45 degree reference . As that is the number you get when you multiple 2x60x8. I am also including the 4 or 1200(when multiplied) as an added horizontal component and did not get the right answer

    where did i got wrong
  2. jcsd
  3. May 24, 2016 #2


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    No way to tell if you do not post your working.
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