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Homework Help: Physics Kinematic Problem - need help

  1. Jun 21, 2005 #1
    Physics Kinematic Problem -- need help

    Well here I am studying for the final and this question pops up and I have no idea how to do it. I know the answer however, but it does not realy help me.

    If you walk 6.0 km in a straight line in a direction north of east and you end up 2.0 km east and several kilometers north. How many degrees north of east have you walked?

    Choices:

    a) 19 degrees
    b) 45 degrees
    c) 60 degrees
    d) 71 degrees

    Answer: d

    Thank you for your help
     
  2. jcsd
  3. Jun 21, 2005 #2
    The trig to this is to try drawing the walk on a piece of paper.
     
  4. Jun 21, 2005 #3

    FredGarvin

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    Science Advisor

    Did you draw a diagram? I drew a triangle with a vertex at the origin and the hypotenuse going north and east (up and to the right) for 6 units. The opposite side would be 2 units....Can you finish from there?
     
  5. Jun 21, 2005 #4
    would it be possible to draw it in the forum?? I still don't get it. I knew how to do this a while ago and it was pretty easy. I did draw a diagram but it didn't really help for some reason. Maybe I read the question wrong, but either way I still don't understand. :cry:

    AH HA!! Thanks Fred. When you said 'opposite' I thought it meant opposite side of the plane. Ah it means the opposite side. Ok thanks I get it.

    Cos -1 (2/6) = 71

    :D

    Thanks again
     
    Last edited: Jun 21, 2005
  6. Jun 22, 2005 #5
    This is simple. First you walk 6km north of east, you end up 2km east and some km's north . Draw a triangle representing the above values where base=2 and hypotenuse=6

    therefore,

    [itex]cosQ= \frac{1}{3}[/itex]
     
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