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What did I do Wrong ?

  1. Feb 25, 2009 #1
    What did I do Wrong ??

    1. The problem statement, all variables and given/known data

    A car travels 2.14km in the x direction then turns left 71.6 degrees to the original direction and travels an additional distance of 2.58km. calculate the x component of the cars net displacement.

    2. Relevant equations

    law of cosines

    3. The attempt at a solution

    plugged knowns into law of cosines equations got 2.78. what did I do wrong ??
     
  2. jcsd
  3. Feb 25, 2009 #2

    gabbagabbahey

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    Re: What did I do Wrong ??

    Draw a picture, you should have a right triangle. There is no need for the law of cosines.
     
  4. Feb 25, 2009 #3
    Re: What did I do Wrong ??

    Ive drawn several pictures does it just look like a right triangle ?
     
  5. Feb 25, 2009 #4

    gabbagabbahey

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    Re: What did I do Wrong ??

    Draw a line downwards from the final position to the x-axis....now do you see the right triangle?
     
  6. Feb 25, 2009 #5
    Re: What did I do Wrong ??

    is your first movemment to the east ?
     
  7. Feb 25, 2009 #6

    gabbagabbahey

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    Re: What did I do Wrong ??

    Yes. Isn't yours?
     
  8. Feb 25, 2009 #7
    Re: What did I do Wrong ??

    yes then your 71.6 degrees left so does yours look acute or obtuse ?
     
  9. Feb 25, 2009 #8
    Re: What did I do Wrong ??

    well if your saying its a right angle it must be acute. im still not sure its a right angle
     
  10. Feb 25, 2009 #9

    gabbagabbahey

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    Last edited by a moderator: May 4, 2017
  11. Feb 25, 2009 #10
    Re: What did I do Wrong ??

    so the answer would be the displacement from (0,0) to the tip of the other vector ?
     
  12. Feb 25, 2009 #11

    gabbagabbahey

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    Last edited by a moderator: May 4, 2017
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