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Simple Vector Diagram, Help with Unclear Wording

  1. Mar 19, 2010 #1

    Ill keep this as brief as possible.

    I am a student taking grade 12 physics through correspondence. I have just started this week, and am finding the material very simple so far (1-d kinematics).

    Periodically, I need to send in small packages of work which I have done. There are very few problems which will actually be evaluated, so obviously I want to make sure Im doing them correctly.

    They gave me this question asking me to draw a vector diagram. I have no trouble with any of the terminology, or at being unclear as to what exactly it is I need to do. My problem comes with the wording which tells me the direction of my second vector. I wouldnt waste anyone's time here with such a simple problem, but being a correspondence student, I dont have a teacher whom I can ask for simple clarification. Ill just type the problem exactly as it is in my book:

    "In a total time of 2.0 min, a duck on a pond paddles 22m [36degrees N of E], and then paddles another 65m [E 25degrees S]."

    That [E 25degrees S] is really confusing me. The first direction was extremely clear, but for the second, I had no idea if I should be using the direction E as my frame of reference and have the vector going 25 degree south of that, or vice versa, or if I should be using my starting point as a frame of reference for all my vectors.

    I *think* my diagram is correct, it would just be stupid to lose valuable marks on the one vector diagram I need to have evaluated due to poor wording. (Or more likely just me being poorly informed.)

    As I said, this is the first week I'm working on this, Ive never been in a physics course before, and I have no teacher to clarify this ridiculously simple question.

    Any help or insight would be much appreciated. Thanks,
  2. jcsd
  3. Mar 19, 2010 #2

    Doc Al

    User Avatar

    Staff: Mentor

    I interpret "E 25degrees S" as 25 degrees South of East. (Start out facing East, then turn 25 degrees South.)

    If you are unsure what is meant, give solutions for both interpretations.
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